The Lahn is a 245.6 km long, right and eastern tributary of the Rhine in Germany . It flows through North Rhine-Westphalia (23.0 km from the source), Hesse (165.6 km) and Rhineland-Palatinate (57.0 km to the mouth). Their mean water flow at the mouth is around 52 m³ / s.
In terms of its length, it ranks seventh among the tributaries of the Rhine.
The Lahn rises in the southeastern North Rhine-Westphalia at the border to Hesse in the southeastern Rothaargebirge on the main ridge of the natural space Ederkopf-Lahn head back (333.01), on which the Rhein-Weser watershed to the Rhine system-internal watershed of Lahn and victory meets. The Lahn spring , the Lahntopf , is located at about southwest of the high Lahnkopf near Lahnhof , a district of Nenkersdorf , which in turn is a district of Netphen . Sections of the Rothaarsteig and Eisenstrasse lead directly past the source of the Lahn .
The Eder (5.5 km northwest of the Lahn spring ) and the Sieg (3 km north of the same) arise in the vicinity . While the Sieg takes the shortest route to the Rhine (heading west), the Lahn initially runs parallel for many kilometers at a distance of less than 10 km from the Eder, which also rises in the same headwaters, in the opposite direction.
Upper course to Bad Laasphe
First the Lahn flows in a north-easterly direction through the Rothaargebirge and its south-east foothills. After it has taken up the Ilm on the left, after some time it reaches the district and hamlet of Glashütte, which belongs to Volkholz, and a little further down the stream, the core town of Volkholz, where it takes up the Ahbach coming from the left . From there the Lahn flows towards Feudingen. From around the Bad Laaspher district of Feudingen , it turns mainly to the east.
Upper Lahn valley and Wetschaft valley
The Lahn section from the town of Bad Laasphe is naturally referred to as the Upper Lahn Valley . From now on, the Lahn valley forms the interface between the Rothaargebirge (north = left) and Gladenbacher Bergland (south) and is included in the second-named mountains.
The state border from North Rhine-Westphalia to Hesse is crossed between Niederlaasphe and Wallau . The Lahn continues to flow over some districts of Biedenkopf (along with the city center), Dautphetals and finally Lahntals in an easterly direction. Here you flow from the right into Wallau the Perf , in Dautphetal- Peace Village the Dautphe which has an expansive side valley to the south, too.
Shortly after the district of Caldern end both with the Wollenberg the mountain ranges of the Rothaargebirge in the north and with the Hungert those of the Gladenbacher Bergland in the south. The Lahn leaves the Rhenish Slate Mountains for a longer stretch and reaches the West Hessian mountains , where it initially flows through the extreme south of the Wetschaft-Senke , north of the soon-to-be-joined Marburg Ridge . The Wetschaft flows from the Burgwald in the north , immediately before it changes its mean direction of flow by 90 °.
The Lahn, which now runs southwards, passes the Marburg-Gießener Lahntal , where, shortly before Cölbe, its longest tributary flows to the left with the Ohm coming from Vogelsberg . From Lollar (negative Lahn km -11.075) to Wetzlar (Lahn km 12.220), the Lahn is another federal inland waterway , as it does not serve general traffic here. The Lahn federal waterway is from Wetzlar to the mouth .
The river breaks through a red sandstone slab ( Marburger ridge in the west and Lahnberge in the east), which border the valley in the entire area of the city of Marburg and its districts. After the Marburg Ridge has flattened out near Niederweimar , the Allna flows towards it from the right , and the Lahnberge also end a few kilometers further with the Zwester Ohm flowing in from the left . To the right of the valley from now on the Gladenbacher Bergland again accompanies the river (including a tributary of the salt flats), to the left the Lumda plateau rises , from where the eponymous Lumda river flows into it at Lollar . Gradually the valley widens to the Giessen basin .
In Gießen , after flowing into the Wieseck from the left , the Lahn again clearly changes its direction of flow from south to west. The Giessen basin retains its full width up to about Atzbach , a district of Lahnau , where the valley narrows somewhat. The Gleiberg , the Vetzberg , the Dünsberg and the Schiffenberg protrude around the central part of the basin .
At Dutenhofener See on the former Prussian-Hessian border lies kilometer 0 of the Lahn. Upstream, the kilometrage continues in the negative area, downstream in the positive area. Extensive gravel mining took place here from the 1960s to the 1980s. The area between Heuchelheim , Lahnau and the Wetzlar district of Dutenhofen should be completely cleared and an Olympic-compatible water sports center with a rowing regatta course should be created. This was partly realized, the Heuchelheimer lakes and the Dutenhofener See are today popular leisure destinations beyond the region. However, nature conservation associations have prevented further gravel formation, and so the area is now one of the largest nature reserves in Hesse.
At the height of the old town of Wetzlar and close to the banks of the old town, the river forms the Lahn Island and is crossed by the Old Lahn Bridge , built in the 13th century . A few hundred meters downstream, the Lahn receives its second longest tributary , the Dill (approx. 55 km long). At this point near Wetzlar, the Lahn and Dill valleys separate three parts of the Rhenish Slate Mountains: Taunus (south), Westerwald (northwest) and the Gladenbacher Bergland ( Lahn-Dill-Bergland Nature Park ).
Weilburger Lahn valley area
Behind Wetzlar, the Lahn valley gradually narrows and merges into the Weilburger Lahn valley area at Leun . From here on, the Lahn valley is also managed with a natural main unit group ( Gießen-Koblenzer Lahntal ) and again counted as part of the Rhenish Slate Mountains.
In the upper area of the Weilburger Lahntal area ( Löhnberger basin ) mineral springs occur, z. B. the famous Selters mineral spring come to light, in the lower area the river turns again to the south and is deepened like a cañon into the flat undulating trough surface. The city of Weilburg is flown around in a distinctive bend in the river, with the Weilburg shipping tunnel, which is unique in Germany, piercing the noose neck. A little below, the Weil coming from the Hochtaunus flows into the Lahn.
At Aumenau, the course of the Lahn turns west again and it passes the fertile Limburg Basin , in the bottom of which the river has cut about 50 m deep and where two tributaries complement the Lahn: the Emsbach from the Taunus and the Elbbach from the Westerwald coming. Here, Devonian mass limestone ( Lahn marble ) often emerges as a rock, as is the case in Limburg an der Lahn , where such a limestone rock is crowned by the Limburg Cathedral . Larger valley widenings also occur here again. Immediately below Limburg, the Lahn reaches Rhineland-Palatinate.
Lower Lahn valley
At Obernhof , opposite the Arnstein monastery , the Gelbach flows into the Lahn and at Nassau the Mühlbach . In Bad Ems is the most important Lahn island Silberau , with the county House of Rhein-Lahn-Kreis. The second large island, the Oberau, follows a little further down the river . Like Fachingen, Bad Ems also has mineral springs ( Emser salt ). Accompanied by the federal highway 260 , the Bäderstraße , the river in the Lahnbogen forms the third large island ( Auf der Lahn ) shortly before Lahnstein , on which a camping site is located, before passing Lahneck Castle .
Finally , the Lahn flows into the Rhine at Lahnstein at height of about ; Down the Rhine lies about five kilometers further north Koblenz with the mouth of the Moselle . Just south of their mouth is the elongated harbor promenade of Lahnsteiner inland port , near its nördlichster place a high office is located.
Catchment area of the Lahn
The following regions are drained by the Lahn
(classified according to the major landscapes Taunus , Rothaargebirge , Westerwald , Gladenbacher Bergland , West Hessisches Bergland and Osthessisches Bergland ) :
*: drains only z. T.
over the Lahn
(possibly%> 70 or <30)
- (in the catchment area)
*: on the watershed
above sea level
in the Lahn river system
|Taunus||Feldberg-Taunus ridge *||Great Feldberg *||881.5||Because , Emsbach|
|Taunus||Wiesbaden Taunus ridge *||High root *||617.9||Aar , Wörsbach (Emsbach)|
|Taunus||Western Aartaunus / Zorner plateau||Mappershainer head *||548.0||Dörsbach , Mühlbach|
|Taunus||Bottom harvester knolls *||Hesselberg *||518||Kleebach , Solmsbach|
|Taunus||Weilburger Hintertaunus||in the Heiligenwald||415.8||Iserbach|
|Taunus||(central) Wetzlarer Hintertaunus||Koehlerberg||424.7||Wetzbach|
|Rothaar Mountains||Ederkopf-Lahnkopf ridge *||compass||694.1||Lahn , Ilse , Banfe|
|Rothaar Mountains||Wittgensteiner Bergland * (> 80%)||Ebschloh *||686.3||Feudinge , Laasphe|
|Rothaar Mountains||Bagpipe *||Bagpipe *||673.3||Treisbach (Wetschaft)|
|Dill Valley||Haincher height *||North Hell||641.1||Dill , Dietzhölze (dill)|
|Westerwald||Oberwesterwald *||Dent||483.1||Gelbach , Aubach (Dill)|
|Westerwald||Niederwesterwald *||Montabaurer height *||545.2||Emsbach , right Gelbach tributaries|
|Westerwald||High Westerwald *||Fox chews *||657.3||Elbbach , Ulmbach , Rehbach (Dill) , Kallenbach , Kerkerbach ,|
|Gladenbacher Bergland||Bottenhorn plateaus||Fishing castle||609.4||Perf , Salt Flats , Allna , Dautphe , Schelde (Dill)|
|Gladenbacher Bergland||Damshausen hilltops||Rimberg||497.1||Ohe (Allna)|
|Gladenbacher Bergland||Krofdorf-Koenigsberger Forest||Dünsberg||497.7||Bieber , Aar (dill)|
|West Hessian mountainous region||Kellerwald * (<20%)||High Lohr *||656.7||Wohra (Ohm)|
|West Hessian mountainous region||Burgwald * (> 80%)||Knebelsrod *||443.1||Wetschaft , red water (Ohm) , right Wohra (Ohm) tributaries|
|West Hessian mountainous region||Gilserberg Heights *||Cold hornbeam *||432.6||left Wohra (Ohm) tributaries|
|West Hessian mountainous region||Lumda plateau||Mardorfer Kuppe||406.8||Lumda , Wieseck , Zwester Ohm|
|West Hessian mountainous region||Northern Vogelsberg foreland *||Dachsberg *||388||Small (ohm)|
|East Hessian mountainous region||Vogelsberg * (approx. 20%)||Seven maple *||752.7||Ohm , Felda (Ohm)|
Tributaries of the Lahn
The two most important tributaries of the Lahn by far and largest in terms of catchment area and drainage are the Ohm from the Vogelsberg from the left and the Dill , as a tributary with the most water, from a southwestern foothill of the Rothaargebirge ( Haincher Höhe ) from the right.
Not only is the fact that the Lahn is 1 km longer over its tributary Ohm than over its own source, but also that the catchment area of the Ohm (984 km²) is significantly larger than that of the Lahn before the Ohm estuary ( 652 km² or even only 452 km² in front of the tributary of the Wetschaft a good two kilometers above). Meanwhile, the flow rate (MQ) of the Upper Lahn with 8827 l / s compared to 7950 l / s is greater than that of the Ohm.
After leaving the source area in the Rothaargebirge all left tributaries come to Gießen, otherwise from less montane parts of the West Hessian mountainous region , after turning to the west or southwest near Gießen, all longer left tributaries come from the Hochtaunus .
In contrast, the right tributaries outside the source area come from the Gladenbacher Bergland as far as the Dill estuary near Wetzlar , and then downstream from the (Hohen) Westerwald . To the south of the Lahn, the Hohe Taunus forms a distinctive watershed. In contrast, the Westerwald does not have a distinctive watershed, so that the watercourses get their direction almost randomly.
Since the center of gravity of the Westerwald is not far from Sieg and, above all, that of the Taunus is very close to the Main , more than half of the two low mountain ranges are each drained by the Lahn. The left tributaries from the Taunus are particularly noticeable due to their strong south-north orientation. The Emsbach river runs exactly over the Idsteiner Senke , which divides the (rear) Taunus into two parts, while the Aar gives its name to the (western and eastern) Aartaunus .
The 12 longest tributaries
The 12 largest tributaries by catchment area
Table of the most important tributaries of the Lahn
All tributaries of the Lahn with a catchment area of at least 29 km² and rivers from the Rothaargebirge from 10 km² are listed below.
(For a better overview or for sorting downstream, hyphens have been inserted into the DGKZ numbers after the 258 - Lahn !)
( MQ )
[l / s]
[l / s • km²]
[m. ü. NHN ]
|Feuding||Left||6.3||21.2||9.8||388||Feudingen||SI||I - Rothaar Mountains||258-112|
|Ilse||right||8.4||11.8||10.5||382||Feudingen||SI||I - Rothaar Mountains||258-114|
|Request||right||11.5||38.9||18.5||326||Bad Laasphe||SI||II - Upper Lahn valley||258-12|
|Laasphe||Left||8.3||19.6||19.4||324||Bad Laasphe||SI||II - Upper Lahn valley||258-132|
|Perf||right||20.0||113.1||1776.1||15.7||24.7||285||Wallau||MR||II - Upper Lahn valley||258-14|
|Dautphe||Left||8.8||41.8||533.4||12.8||37.5||245||Peace Village||MR||II - Upper Lahn valley||258-16|
|Wetschaft||Left||29.0||196.2||1701.6||8.7||56.3||192||under. Göttingen||MR||III - Wetschaft Depression||258-18|
|ohm||Left||59.7||983.8||7949.8||8.1||58.7||188||Oberh. Cölbe||MR||IV - Marburg Lahntalsenke||258-2|
|Allna||right||19.1||92.0||665.3||7.2||77.1||172||Argenstein||MR||IV - Marburg Lahntalsenke||258-32|
|Zwester Ohm||Left||20.0||69.5||405.2||5.8||84.0||165||Sichertshausen||MR||IV - Marburg Lahntalsenke||258-334|
|Salt flats||right||27.6||137.8||1322.4||9.6||87.4||164||Odenhausen||GI||IV - Marburg Lahntalsenke||258-34|
|Lumda||Left||30.0||131.5||950.4||7.2||93.6||160||Lollar||GI||V - Giessen Lahntalsenke||258-36|
|Wieseck||Left||24.3||119.6||663.5||5.5||102.2||155||to water||GI||V - Giessen Lahntalsenke||258-38|
|Beaver||right||13.6||34.7||217.1||6.3||105.1||151||Hypocritical home||GI||V - Giessen Lahntalsenke||258-394|
|Kleebach||Left||26.9||164.6||815.9||5.0||106.2||150||north of Allendorf||GI||V - Giessen Lahntalsenke||258-396|
|Wetzbach||Left||11.7||32.9||261.7||8.0||119.6||147||Wetzlar||LDK||V - Giessen Lahntalsenke||258-3996|
|dill||right||55.0||717.7||9513.9||13.3||120.4||147||Wetzlar||LDK||V - Giessen Lahntalsenke||258-4|
|Solmsbach||Left||24.6||112.5||839.5||7.5||128.1||141||Burgsolms||LDK||V - Giessen Lahntalsenke||258-52|
|Iserbach||Left||19.2||31.2||264.8||8.5||131.4||139||Leun||LDK||VI - Weilburger Lahntal||258-54|
|Ulmbach||right||22.9||60.9||740.5||12.2||138.2||135||Biskirchen||LDK||VI - Weilburger Lahntal||258-56|
|Kallenbach||right||14.6||84.7||942.3||11.1||141.3||132||Löhnberg||LM||VI - Weilburger Lahntal||258-58|
|Because||Left||46.6||247.9||2317.3||9.3||149.4||130||Unterh. Weilburg||LM||VI - Weilburger Lahntal||258-6|
|Kerkerbach||right||20.7||70.2||564.0||8.0||176.0||112||under. Runkel||LM||VII - Limburg Lahn Valley||258-72|
|Emsbach||Left||39.1||321.8||1805.2||5.6||181.0||110||above Limburg||LM||VII - Limburg Lahn Valley||258-74|
|Elbbach||right||40.7||323.7||3996.4||12.3||185.4||109||Limburg||LM||VII - Limburg Lahn Valley||258-76|
|Aar||Left||49.7||312.6||1710||7.1||103||Diez||EMS||VII - Limburg Lahn Valley||258-8|
|Dörsbach||Left||32.0||114.0||805||7.1||94||Obernhof||EMS||VIII - Lower Lahn valley||258-92|
|Gelbach||right||39.7||221.2||2380||11.0||93||Unterh. Obernhof||EMS||VIII - Lower Lahn valley||258-94|
|Mühlbach||Left||32.1||171.9||957||6.6||85||Nassau||EMS||VIII - Lower Lahn valley||258-96|
|Emsbach||right||11.5||29.4||75||Bad Ems||EMS||VIII - Lower Lahn valley||258-98|
- The measured value for the discharge (MQ) of the Aar relates to the measuring point Zollhaus - 239.2 km²; 12.12 km above the mouth.
- The measured value for the discharge (MQ) of the Dörsbach refers to the measuring point Arnstein Monastery - 113.2 km²; 1.5 km above the mouth.
- The measured value for the discharge (MQ) of the Gelach refers to the measuring point Weinähr - 214.6 km²; 3.5 km above the mouth.
- The measured value for the discharge (MQ) of the Mühlbach refers to the measuring point Schulmühle - 145.8 km²; 9 km above the mouth.
Cities and towns along the river
nature and environment
fauna and Flora
In 1999 the Lahn was classified in biological quality class II and chemical quality class I. Overall, it is considered close to nature. The migration of fish like that of the salmon is prevented by the barrages; By installing fish ladders, an attempt is made to facilitate the reintroduction of formerly native fish. In 2007, together with the fish ladder at Klinkel's weir in Gießen, the Lahn window was set up as a Hessian water information center and reopened in 2014 after an expansion. After gravel mining was stopped in the mid-1990s, one of the largest nature reserves in Hesse has developed between Lahnau, Heuchelheim and Wetzlar-Dutenhofen in the middle Lahn Valley, also known as the Lahnaue nature reserve .
The water quality of the Lahn in the North Rhine-Westphalian area is described as good; On the Hessian side, however, the "Association for Water Protection" found increased nitrate levels in the Lahnstein area at the beginning of 2017. The limit value of the Water Framework Directive is 11 mg / l for “good status”. While 5.7 mg / l were measured in Bad Laasphe, the value in Biedenkopf, a few kilometers away, is 11.6 mg / l. In Wetzlar and Lahnstein it is 19.7 and 17 mg / l well above the intended limit. The reason for this is the agricultural use in the Hessian section of the Lahn. According to the association, bacteria are another burden that limits drinkability.
|Passenger shipping on the Lahn|
The Lahn is a so-called other federal inland waterway from km −10.71 above Gießen to km 12.22 near Wetzlar. From there to the confluence with the Rhine (km 137.3) it is designated as an unclassified federal waterway . In these areas it is subject to the Federal Waterways and Shipping Administration ; The Koblenz Waterways and Shipping Office is responsible . As with most federal waterways, the kilometers run in the direction of flow and begins 4 kilometers below Gießen at the confluence of the Kleebach ( ) near Heuchelheim on the former border between Prussia and the Grand Duchy of Hesse with km 0 and ends at km 137.3 with the confluence into the Rhine at km 585.72. Above the Kleebach (km 0), the river kilometers upstream are counted and given a negative sign.
From km 11.08 the Lahn is regulated with 24 barrages, mostly with fixed, partly still from the Middle Ages dating weir, for a total head to the Rhine with mean water of 81.31 m. There are ship locks (mostly 34.00 x 5.34 m) on 22 steps (excluding Gießen and Wetzlar), 16 of which are in their own lock channels next to the river. 18 run-of-river power plants use the Lahn to generate electricity.
The waterway is used almost exclusively for tourism by smaller motor yachts as well as paddle and rowing boats . From the mouth upwards to above Dehrn (km 70, up to the rapids in front of Steeden ), the river is continuously navigable even by larger ships (180 t) with locks operated by personnel. A semi-automated self-service of the locks with remote monitoring is planned. The fairway depth is 1.60 m apart from the missing depths announced by the Waterways and Shipping Office. Only the Kalkofen (normal water level 1.80 m) and Leun levels are decisive for shipping . From Steeden upwards there are self-service sluices, there are no more fairways and there are repeated shallows that make passage even more difficult for small motor boats. In Wetzlar, two weirs finally block continuous shipping upstream; instead of a lock, the transfer of boats is made possible by means of roller systems.
Non-motorized water hikers are allowed to use the Lahn on the entire course of the river between Roth (near Marburg) and the mouth.
The Lahn is regulated by the following locks arranged downstream:
|Lock ↓||River kilometers|
|Sluice lime kiln||105.8|
|Bad Ems lock||126.9|
Freight traffic has not taken place on the Lahn since 1981. With regard to water tourism on the Lahn, the following were counted in 2016:
- Passenger ships: 1 618
- Pleasure craft: 50 174
- The ship counts were only carried out at the manned locks between Lahnstein and Limburg.
In addition to the Lahn-Ferien-Straße , there is also the Lahntal cycle path in the Lahntal . This is accompanied by the Upper Lahn Valley Railway between Feudingen and Marburg, the Main-Weser Railway between Marburg and Gießen and from Gießen and the Lahn Valley Railway from Wetzlar to Lahnstein .
For hikers there are the Lahnhöhenwege on both sides of the Lahn from Wetzlar towards Oberlahnstein . In January 2011, the new Lahnwanderweg, inaugurated in 2010, was awarded the title Quality Trail Wanderable Germany by the Association of German Mountain and Hiking Associations .
The Lahn has been used for sustainable tourism since the late 1980s; the existing uses are coordinated and expanded by the public tourism organizations. At the level of the districts, tourism associations were initially formed, which in 2002 became the Lahntal Tourismus Verband e. V. have merged.
Once a year, as part of the Lahntal Total event, sections of the B 62 and L 719 between Bad Laasphe- Feudingen and Cölbe are closed to make the route accessible to cyclists, pedestrians and inline skaters.
In the middle and lower Lahn valley, viticulture (wine growing) is practiced in some communities . It forms its own large location in the Middle Rhine wine-growing region . Looking down the river Lahn there is viticulture in the following places:
|Fachbach||Free of single layers|
Wine has been grown in Dietkirchen on a small plot on the southwest slope of the Stiftsfelsen since 1998 . The harvest is between 300 and 400 kilograms per year and is mainly processed into mass wine .
Use and expansion
Prehistory and Antiquity
The Lahn area was already settled in the Stone Age, as evidenced by finds near Diez, in Steeden and in Wetzlar . More recent finds in Wetzlar-Dalheim on the western city limits show a 7,000 year old ceramic band settlement.
Presumably the Lahn played an important role as a constant trade and transport route at the latest by the time of the Roman Empire . For the transport on the Lahn (lat. Laugona ), due to its flat course, a towboat trip with flat barges, the so-called Prahmen , can be assumed. In the Roman occupation phase around the turn of the times, the Lahn was not only of civil importance but also of military importance. The Roman military probably used the Lahn as a fast transport and supply connection for their marchers. Archaeological finds from this time are the Roman camp Limburg , the Roman camp Lahnau-Dorlar and the Forum Lahnau-Waldgirmes . Later the Lahn was crossed by the Upper German Limes and probably used to supply the Ems fort . Due to the Limesfall in 259 and 260 AD, the Lahn lost its previous importance for the Romans and they withdrew militarily to Niederlahnstein . From there they controlled the Lahn in its estuary and probably went on patrols on it.
In the 1st and 2nd centuries the Landoudioer are documented as inhabitants of the middle and upper Lahn valley. In the middle of the 8th century the inhabitants of this area are still called Lognai . During the migration of peoples settled Alemanni in the lower Lahntal. But they were ousted by the Franks .
Around the year 600, names like Laugona, Logana, Logene or Loyn were common, which are very similar to the historical names of the river Leine . The name has changed several times over the years, the meaning is uncertain. A pre-Germanic origin is possible. The name Loganaha (lye water, washing water), later Loginahe , which appeared in the 8th century , refers to the cloudy color of the river Lahn, according to Egli.
The construction of the first mill weirs in the river in Marburg, Gießen and Wetzlar is assumed to be in the 11th century . However, these did not extend across the entire width of the river and left gaps for boat traffic.
A pilgrim hostel built in the 13th century on the site of today's St. Jakobs Hospital in Marburg probably served as a stopover for pilgrims traveling across the Lahn to Santiago de Compostela . The location of Stolzenfels Castle near Koblenz, which was built around 1250, can be seen as a first indication of customs registration not only for the Rhine, but also for the mouth of the Lahn. For the construction of the city wall of Koblenz from 1276 to 1289, the transport of lime from the Diez area over the Lahn is guaranteed. The first mention of the Diez stacking rights comes from the early 14th century , which is evidence of noteworthy shipping . The earliest use of today's spelling of the name is recorded for the year 1365.
1593 to 1599, Johann VI. From Nassau-Dillenburg on the lower Lahn to Diez, create towpaths for horses and remove obstacles in the river. It is possible that the holdings of the House of Nassau in the Netherlands, which have been growing since the middle of the 15th century, and the highly developed hydraulic engineering there provided an important impetus for this. At least in sections, towpaths must have already existed. But even after the expansion, the towing systems remained inefficient, as the paths changed banks in around 50 places. At the same time, however, the Counts of Diez attached great importance to maintaining the mill weir at Dierstein Monastery , which effectively closed the river above Diez into the 18th century.
In 1606 the lower Lahn was deepened for the first time for shipping on a smaller scale. The river was navigable there for four to five months a year. However, there were also numerous mill weirs with only narrow gaps, so that traffic was limited to small boats. In the 17th and early 18th centuries there were several initiatives by neighboring princes to further develop the Lahn as a waterway and to make it navigable from the mouth to Marburg, but all of them failed in the voting phase. At the same time, the construction of pre-industrial steelworks on the lower Lahn also hindered shipping traffic, because additional weirs with mostly narrow gaps were built to supply these plants with water power.
In 1718, in his role as guardian in the county of Nassau-Diez, in the residential town of Diez at the mouth of the Aar , Karl von Hessen-Kassel set up a port and the manorial fruit tree as a warehouse. 1728 was Kurtrier in response to the Nassau lock in Dierstein in turn below Diez on kurtrierischen Balduinstein a continuous military build to that there was repeated armed together with coup-like devastation in the following years. In 1740 Kurtrier began construction work to make the mouth of the Lahn navigable for larger ships. During the Second Silesian War , billeted French troops partially destroyed the weirs at Balduinstein and Dierstein in the winter of 1744/45 in order to be able to supply themselves with ships. In the winter of 1753/54, bank reinforcements with towpaths were laid along the entire length of the river . After that, the river was navigable for ships with a load of up to 240 quintals downstream and up to 160 quintals. The most important transport goods were ores and other mineral raw materials downstream, and from 1720 onwards, mineral water from Fachingen and Niederselters was made. Mainly charcoal, coal, salt and wine were transported up the Lahn.
Expansion in the Duchy of Nassau
During the French occupation , inspections of the river began in 1796, which were to be followed by extensive expansion, which, however, did not take place due to political developments. The newly founded Duchy of Nassau finally made the Lahn navigable again from 1808 according to plans by Oberbauinspektor Johann Jakob von Kirn. The banks were fortified so that the course was to be narrowed, especially in shallow areas, and standardized, 6.5-meter-wide gaps that could be closed by hand were built in the weirs. In 1808 the expansion reached Limburg, in 1809 Runkel, where the first lock ever was built on the Lahn, and on October 12, 1810, shipping to Weilburg for 18-ton ships was ceremoniously opened. In the long term, it was planned to make the Lahn navigable to Marburg and from there to create a canal to the Fulda and thus to the Weser . This should create a waterway from France via the Rhine Confederation to the North Sea . Upstream from Limburg, however, the work progressed only slowly, also because the population brought in for relief services was reluctant to cooperate. Large parts of the bank were only secured with fascines , which soon rotted away.
In 1816 the Duchy of Nassau and the Kingdom of Prussia agreed to expand the Lahn as far as Gießen, where the Grand Duchy of Hesse joined. Little is known about the following work, but in 1825 the Lahn boatmen, who supplied the mineral water springs in Selters and Fachingen , sent an address of thanks to the Nassau government in Wiesbaden for the repair of the river systems. Overall, however, only repairs and makeshift work appear to have taken place until the 1830s. The only major project completed at this time was the construction of a chamber lock in Limburg in 1838/39.
The earliest attempts to record shipping traffic on the Lahn date back to 1827. 278 ships were counted at the Runkeler Schleuse that year, with the Nassau state government expressly pointing out that most traffic from the estuary to Limburg or with smaller boats from The upper reaches of Weilburg are on the way and only a small part of Runkel passes. In 1833 464 ships were counted there. The most important reason for the increase may have been the increasing iron ore mining in the Weilburg area. An estimate from 1840 assumes that the total amount of iron ore transported on the river made up around 2000 boatloads, although the river was only navigable from the mouth to Weilburg. In addition, mainly grain and mineral water were transported down the river. Upstream of the Lahn, the boats mainly contained hard coal , charcoal , plaster of paris and colonial goods . Around 1835, around 80 larger, shallow-draft boats were in operation on the Lahn.
In view of the increasing ore production on the Lahn, Prussian and Nassau officials made an inspection trip from Marburg to the mouth in 1841. Above all Prussia pushed the project forward to create a connection between its exclave Wetzlar and the Rhine province and to secure the iron ore supply for the growing industry in the Ruhr area . Shortly thereafter, Hessen-Darmstadt also joined the expansion efforts, while Hessen-Kassel declined to participate. In preparation for the foreseeable work, the residents set up a continuous gauge on the Lahn for the first time in 1842 . The participating governments contractually stipulated on October 16, 1844, to make the river passable for boats by regulating damming up to Gießen, which should be significantly larger than the previous vehicles on the Lahn. In Prussian territory, the work was largely completed by 1847. Locks were built at Dorlar, Wetzlar, Wetzlar-Blechwalze, Oberbiel and Niederbiel . By 1853, further locks were built in Löhnberg , Villmar , Balduinstein , Nievern, Ahl, Hohenrhein, Niederlahnstein and Neunheim and the 195 m long Weilburg shipping tunnel (1842–1847) was the greatest technical achievement . The weir of the former Dierstein monastery was demolished. However, the bank consolidation and river deepening progressed slowly in the Nassau section of the route. In addition, the older Limburg lock did not reach the contractually agreed width of 5.34 meters, but Nassau refused to expand it. In the following years there were several disputes between Nassau and Prussia, until Nassau had finally fulfilled its obligations in 1855. As the last step, weirs were built in Bad Ems, Hollerich, Fürfurt and Kirchhofen from 1853 to 1859, which removed rapids with their backwater, but had to be made passable by sluice. The weirs were also used in Bad Ems and at the Elisenhütte near Hollerich as sources for water power. In 1859 the contractually agreed condition was reached and the Lahn was navigable for 142 kilometers or 59 percent of its length.
Despite the expansion, the Lahn boats could only sail fully loaded from Gießen to Löhnberg. There they had to lighten part of their cargo in order to reduce their draft for the onward journey. Again, this was only possible for two to three months. In another four to five months per year, the load had to be reduced earlier due to the low water level. The rest of the year the Lahn was not navigable at all. From Wetzlar to Lahnstein, where the cargo was loaded onto the large Rhine barges, the boats took three to four days. A trip from Wetzlar to the estuary and then back again with horse power took around 14 days under good conditions. At that time, two types of transport boats were in use: those with a load capacity of 350 quintals and a larger variant with 1,300 quintals.
While the Lahn Valley Railway with nine large bridges and 18 tunnels was built along the river from 1857 to 1863 , Prussia and Nassau tried to keep the Lahn shipping going by lowering tariffs. Ultimately, however, the railroad prevailed as a means of transport and freight shipping on the Lahn continued to decline (in 1889, 24,700 tons per year). Several projects to operate steamers on the Lahn were stuck in their beginnings from 1854.
Expansion in Prussia
In October 1866, through the annexation of Nassau and parts of the Grand Duchy of Hesse , Prussia was solely responsible for the entire navigable course of the Lahn, except for three kilometers near Gießen, which were further in the Grand Duchy. The confluence of the Lahn into the Rhine was redesigned in two construction phases. The originally right-angled mouth received a swing down the Rhine in 1875, which reduced the siltation. From 1882 to 1885 the Oberlahnsteiner Hafen was expanded and connected to the Lahn estuary with a short canal.
In 1875, 1885 and 1897 the Prussian government discussed plans to convert the Lahn into a canal, which would have made it possible to sail with larger ships and which would have made its use less susceptible to low water. However, these plans were never implemented. Only a single barrage was built near Kalkofen in 1882, the river bed was dredged at certain points, around 1880 near Runkel. In 1903, industrialists founded an association in Wetzlar to increase shipping on the Lahn. From 1905 to 1906, the lowest 13 kilometers to Bad Ems were expanded by increasing dams and makeshift measures at locks so that ships with a draft of up to 1.60 meters and 180 tons of cargo could operate.
20th and 21st centuries
The invention of the diesel engine , which displaced the horse grains that had previously been in use, gave the Lahn shipping industry an upswing after the First World War . In 1921 it was taken over by the Reich, as is the case with all waterways with goods traffic. From 1926 to 1928, the river was 67 kilometers long at Steeden above Limburg , where large quarries delivered the main cargo, and was continuously dammed for 190-tonne ships by building further barrages. In 1946, a flood of the century on February 8th and 9th caused severe damage in the Lahn area.
A sixth and probably last making it navigable lasted from 1938 to 1964. The Lahn was to be made accessible to the 300-tonne ship with a diving depth of 1.80 meters, which is widespread in the Western European waterway network. However, the expansion of the locks at Lahnstein, Hohenrhein, Bad Ems and Nievern remained. After the quarries near Steeden were closed in 1971, all further expansion plans were dropped. The following work on the systems in the river aimed only at the use by pleasure boats.
In 1951 a general plan was drawn up with proposals for dams and flood retention basins (including the Lahn dam above the urban area from Laasphe to behind Saßmannshausen). The planned Lahn Association, which was supposed to cover the entire catchment area of the Lahn, was not formed, so that the general plan was not implemented.
- 1960: Start of gravel mining in the broad plains of the Lahn valley near Gießen and Marburg.
- 1984: On February 7th, the flood of the century on the Lahn, which resulted in damage amounting to millions; since then central flood warning service and coordination of flood protection by the regional council of Giessen
- 1996 Cessation of gravel mining on the Lahn, designation of large parts of the Lahn valley in the Hessian section as a nature reserve
- 2017: In October 2017, the Lahn was damaged by a liquid manure accident and its runoff over the Weil and many fish died.
In preparation for the expansion campaign in 1840, the Duchy of Nassau employed Eduard Ferdinan Haas as hydraulic engineering inspector, who was responsible for the Rhine, Main and Lahn. His office was set up in Diez and equipped with its own harbor basin as a berth for construction ships and similar equipment. In 1860 an office building was built that still houses the successor authority today. As the Diez Hydraulic Engineering Inspectorate, the authority was transferred to Prussia in 1866, was subordinate to the district president in Wiesbaden and was given responsibility for the entire Lahn. From 1910 on, the facility operated as the Diez Wasserbauamt. In 1921 it was spun off from Prussia to the German Reich and subordinated to the Rheinstrombauverwaltung Koblenz. In 1939 it was renamed the Diez Waterways Office and in 1949 the Diez Waterways and Shipping Office. After the end of the war and until 1952, authorities in Wiesbaden and Eltville were partly responsible for the Lahn due to the fact that it belonged to different zones of occupation. In 1952, the Mainz Waterways and Shipping Directorate was given responsibility for the entire river and with it the Diez authority that was attached to it from then on. On February 1, 1978, the Diez Water and Shipping Office was subordinated to the Koblenz Water and Shipping Office as a branch. At that time, the closure of the branch office was announced, but this has not happened until today.
Palaces and castles
On both sides of the Lahn, the following castles and fortresses or their ruins, arranged from the source to the mouth, tower up:
- Natascha Rhein, Susie Maass: Hessen from above: Main, Rhine and Lahn. Report film with aerial shots, the flight along the Lahn begins in the headwaters in the Rothaargebirge and leads via cities such as Biedenkopf, Marburg, Gießen, Wetzlar, Weilburg and Limburg to the confluence with the Rhine, 90 minutes, Germany, Hessischer Rundfunk, 2014.
- Jakob Hölscher (Hrsg.): Picturesque views of the Rhine and the Lahn. Taken from nature by Carl Bodmer , engraved by the finest artists in France and Switzerland. ( R. Bodmer , Ruef, Salathé, Himely, Martin et al.). Koblenz 1836/37.
- Hans Feldtkeller : The Lahn. ( Deutsche Lande - German Art ). Munich / Berlin 1965.
- Martin Eckoldt: The history of the Lahn as a waterway. In: Nassauische Annalen 90. 1979, pp. 98-123.
- Albrecht Greule: Strata of waters in the Lahn river basin. In: Norbert Nail (ed.): The world of names. Six articles based on names. (Writings of the Marburg University Library. Vol. 87). Marburg 1998, ISBN 3-8185-0251-X , pp. 1-17.
- Helmut Schuld, Arno Kappler: The Lahn - From the source pond to the mouth. Illustrated book. Frankfurt am Main 1998, ISBN 3-7973-0679-2 .
- Anneli Karrenbrock: Romanticism on the Rhine and Lahn - On the trail of reality and enthusiastic transfiguration . In: Heimatjahrbuch 2003 Rhein-Lahn-Kreis, Bad Ems 2003, pp. 43–50, 3 figs.
- Hydrological Atlas of Rhineland-Palatinate. Edited by State Office for the Environment, Water Management and Trade Inspection. Oppenheim 2005.
- Michael Losse: Castles and palaces on the Lahn […] Imhof, Petersberg 2007, ISBN 978-3-86568-070-9 .
- Wasser- und Schifffahrtsdirektion Südwest: Compendium of the Wasser- und Schifffahrtsdirektion Südwest. Organizational and technical data, inland navigation, tasks, waterways. Self-published, Mainz 2007.
- Topographical Information Management, Cologne District Government, Department GEObasis NRW ( Notes )
- Map service of the landscape information system of the Rhineland-Palatinate Nature Conservation Administration (LANIS map) ( notes )
Water map service of the Hessian Ministry for the Environment, Climate Protection, Agriculture and Consumer Protection ( Notes ) (Perf-estuary at km 220.9) and Topographical Information Management, Cologne District Government, Department GEObasis NRW ( Notes ) (24.7 km to Perf- Mouth)
→ "Lahn-km" (NRW) = 193.25 - indication / TIM
→ "Lahn-km" (HE) = 245.6 - indication / WFD
- GeoExplorer of the Rhineland-Palatinate Water Management Authority ( information )
- Sum of the levels Kalkofen (Lahn, see box) and Arnstein Monastery (Dörsbach), Weinähr (Gelbach) and Schulmühle (Mühlbach; see each table )
- Lime kiln gauge - main annual values for discharge 2006 ( Memento from August 1, 2012 in the web archive archive.today )
- The location of the gauge above the mouth is calculated from the length of 122.9 (1) km of the navigable Lahn minus the 106.4 km specified for the Kalkofen gauge.
- Note: Mean runoff coefficient of the level Kalkofen multiplied by the entire catchment area (arithmetically: 52.05 m³ / s)
- Water map service of the Hessian Ministry for the Environment, Climate Protection, Agriculture and Consumer Protection ( information )
- Hermann-Josef Hucke (Ed.): Great Westerwaldführer . 3. Edition. Westerwald Association V., Montabaur 1991, ISBN 3-921548-04-7 .
- "Rothaargebirge" does not refer to the mouth section, but to the source and course. On the right, the Lahn watershed above Perf is seen as the border between the Rothaar Mountains and the Gladenbacher Bergland.
- In Wittgenstein the water quality of the Lahn is good. In: derWesten.de . March 7, 2017. Retrieved March 9, 2017 .
- Lengths (in km) of the main shipping lanes (main routes and certain secondary routes) of the federal inland waterways, federal waterways and shipping administration
- Directory F of the Chronicle ( Memento of July 22, 2016 in the Internet Archive ), Federal Waterways and Shipping Administration
- Directory E, Ser. No. 26 of the Chronicle ( Memento of July 22, 2016 in the Internet Archive ), Federal Waterways and Shipping Administration (PDF, 70 kB, p. 7)
- https://www.gdws.wsv.bund.de/SharedDocs/Downloads/DE/Verkehrsberichte/Verkehrsbericht_2016.pdf?__blob=publicationFile&v=3 Shipping on the Lahn
- Rhein-Lahn-Zeitung: Lahnwanderweg receives top marks , from January 14, 2011, accessed on January 25, 2011.
- Mittelrhein-Wein e. V .: Middle Rhine wine-growing region - Lahntal
- Wilhelm Niemeyer: The Pagus of the early Middle Ages in Hessen. Marburg, 1968, p. 169.
- Johann Jakob Egli : Nomina geographica. Language and factual explanation of 42,000 geographical names of all regions of the world. Friedrich Brandstetter, 2nd ed. Leipzig 1893, p. 521
- Biedenkopf district. The hinterland - God's toy box . (Hessische Hefte Volume 2). Hessenland-Verlag Kurt Meister, Kassel 1957.
- All fish are dead Tag24.de
- Hessen from above: The Lahn , on hr-online.de
- Lahntal Tourismus Verband: Leisure time around the water , Lahn hiking trail (each with maps of the course)
- Hessen Tourismus: Lahntal Cycle Path (with elevation profile)
- Uli Frings: Along the Lahn - Lahnhöhenweg and Limes
- Limburg boat club: Lahn cruising area (with maps and information on locks)
- Strategic environmental assessment for the flood risk management plan for the Hessian catchment area of the Lahn
Nature and geography
- Map / aerial photo of the Lahn and its main tributaries / placemarks ( Google Earth required)
- Hessian State Office for Environment and Geology: Level of the Lahn area
- Hessian State Office for Environment and Geology: Cadastre of the existing and potential retention areas in Hesse