Watchtower Koblenz-Kleiner Laufen

Watchtower Koblenz-Kleiner Laufen
Alternative name	Summa Rapida
limes	Danube-Iller-Rhine-Limes
section	Route 2
Dating (occupancy)	Valentine 371 AD
Type	Turres / Burgus
unit	Legio VIII Augusta  ?
Size	8 × 8 meters
Construction	stone
State of preservation	Square complex, walls still preserved up to a height of 2 meters, conserved in 2014 and partially restored.
place	Koblenz
Geographical location	661 377  /  274 037 coordinates: 47 ° 36 '50.9 "  N , 8 ° 15' 17.9"  O ; CH1903:  661 377  /  two hundred and seventy-four thousand and thirty-seven
Previous	Zurzach Castle (Tenedo) (East)
Subsequently	Watchtower Koblenz-Rütenen (west)

Solidus Valentinians I.

View of the Koblenzer Laufen

Topographia Helvetiae, Rhaetiae et Valesiae , the little one running near Koblenz (Merian 1654)

Jakob Heierli during the excavations of 1906/1907

Marking and addition of the building inscription

Tower site before renovation from 2014

Images of watchtowers on Trajan's Column

Findings sketch after K. Stehlin, 1907-2014

Tower location after the renovation in 2014
Kanton Aargau; Photo: Béla Polyvàs , 2014
Link to the picture (please note copyrights )

The watchtower Koblenz-Kleiner Laufen was part of the Roman Danube-Iller-Rhein-Limes and is located in the canton of Aargau , municipality of Koblenz in Switzerland .

The late antique watchtowers on the Upper Rhine are among the most important Roman legacies on the territory of today's Switzerland. They were built in the 3rd and 4th centuries and were part of a surveillance and alarm chain that was supposed to secure the southern bank of the Rhine against invaders from free Germania. In the canton of Aargau around 30 watchtowers and other military installations from Roman times have been identified that were part of the fortress line of the Rhine Limes. Due to the building inscription found on site, not only the exact year of construction of this watchtower, but also its ancient name has become known.

Surname

The name of today's Koblenz is clearly of Roman origin. It refers to its location at the confluence of the Aare into the Rhine . The Latin confluentia means "confluence". The watchtower on Kleiner Laufen is the only one in the entire canton from which the ancient name, “Summa Rapida” (upper rapids or on the rapids), was passed down and also refers to its location. The name can be explained - after Otto Schulthess - with the fact that there are two more rapids further down the Rhine:

• the «Grosse Laufen» at Laufenburg ( media rapida ?) and
• the “Gwild with the Hellhaken” near Rheinfelden ( infima rapida ?).

location

Koblenz is located at the mouth of the Aare in the Upper Rhine , right on the border with Germany . The late antique watchtower stood a little below the Kleiner Laufens (also called “Kadelburger Laufen”), around one kilometer east of today's village, directly on the slope of a steeply sloping gravel terrace . This location offered a good view of the section of the river lying above the confluence of the Aare and Rhine and of the Wutach valley to the right of the Rhine. Matthäus Merian reported in 1654 that the Rhine could easily be crossed over boards when the water was low in the winter months. Felix Staehelin mentioned that there was a: “... a ford-like crossing of the Rhine that could be safely crossed with rafts and 'flying bridges' (ferry boats)”.

development

The area around Koblenz has been continuously inhabited since Roman times. From the middle of the 1st century there was a villa rustica . Even at that time, the Rhine was of great importance as a national transport route. The fastenings of the late antique Rhein limes were during the reign of Kaiser I. Valentinian (. 364-375 n. AD) extended amplified and counted to a monitoring and communication system which differs from Basel (Basileum) to Lake Constance (Lacus Brigantiae) extended . This was in this section under the command of the Dux provinciae Sequanicae . The watchtowers and the other military installations of the Romans had to be placed in visual contact with each other. Immediately afterwards there were three more towers on the Rhine loop:

• the watchtower Rütenen, in Koblenz,
• the watchtower in Sand-Felsenau, in Leuggern (2 km away) and
• the watchtower Jüppen, in Full-Reuenthal (3 km away).

In this way, in the event of an attack by the Teutons, the crews of Kaiseraugst ( Castrum Rauracense ) and Bad Zurzach ( Tenedo ) could be alerted by light signals or horn signals and directed to the respective hot spots. After the Roman troops withdrew from the Rhine border in winter 401/402, the towers were abandoned and left to decay. Whether people have settled in today's Koblenz municipality from the end of Roman times to the present can no longer be proven today. Since the late 4th century there has been no written or archaeological evidence. Koblenz is first mentioned in writing in the Zurzacher Miracle Book from around 1010.

Research history

The ruin at Kleiner Laufen has been known since the middle of the 19th century. Its foundation walls were also well preserved. The archaeologist Ferdinand Keller recorded the condition of the heavily encumbered wall rubble during his investigations into the late ancient Limes on the Upper Rhine and correctly recognized the remains of a Roman watchtower in it.

The first excavation work and archaeological investigations were carried out by Jakob Heierli in 1896 and 1907 . At that time the walls were still up to 3 meters high in places. In 1914, during excavation work, the baths of a Roman manor (villa rusticae) , which was inhabited from the 1st to the 3rd century, Roman terra sigillata and brick stamps came to light. The archaeologists also uncovered the remains of a Roman watchtower in the "Rütenen"; Another was probably in the hallway "Frittelhölzli". In 1922 Otto Schulthess wrote that the watchtower was probably “… irreparably doomed”. The roots of the dense vegetation would have largely destroyed the walls. The government of the canton of Aargau agreed to cover the cost of the renovation, but was unable to raise the around 500 francs for it. Schulthess therefore had to limit himself to supplementing the existing building surveys. A comprehensive restoration was only carried out in 1932/1933, with the historical association Zurzach (HVZ) in charge. The Swiss Confederation, the canton, the Koblenz municipality as well as the Hallwil Foundation and the Swiss Soda Factory in Zurzach paid for the costs. As part of this work, Josef Villiger completed the findings sketch at the request of Karl Stehlin and prepared a new floor plan. In addition, all joints and irregularities were coated with Portland cement and the top of the wall was covered with stone slabs. To the east and west of the watchtower, two exploratory cuts were also made, with the aid of which the remains of a wall and ditch could be identified. It was not possible to sound out in the south, as Kantonsstrasse 7 passes there.

Even then, there were some concerns about how the watchtower would be represented to the public. In addition to a model still exhibited in the Museum Höfli in Bad Zurzach and an information board - which has since disappeared - the course of the trench was made visible to the visitors with upright limestone slabs. In 2014 they were still 4 meters long east of the tower; in the west, however, a large part of the limestone slabs had been torn out. Since no major repair work had been carried out since the restoration (1932/1933), the masonry was in an extremely poor condition in 2014. The renovation work was carried out between June 6 and July 11, 2014 by students and lecturers from the University of Basel . In addition to the documentation work, the main task was to remove the vegetation, clean the masonry and in some places to uncover the lowest stone layers of the rising or the uppermost part of the foundation. In addition, inspections were carried out in the vicinity of the plant. During the renovation work on the tower of Koblenz-Kleiner Laufen, in comparison with two other late antique towers in the canton of Aargau, it was important to realize that the towers built under Valentinian I have a lot in common, but with regard to their construction a very individual character have such. B. in relation to the size or the presence of wood reinforcements in the foundation area.

Find spectrum

The archaeological finds are only sparse. According to Jakob Heierli, only a few bones, fragments of groin bricks, as well as processed tuff fragments and profiled sandstones were found during the excavations . Another spoil , a "cube made of shell sandstone with inserts " outside the entrance , was deposited inside the watchtower in 1932. It came to light again in 2014 during the inspections at the foot of the slope edge. In the early excavation records, there were also indications of the discovery of an amphora base and a coin allegedly from the Constantinian period .

Building inscription

The most important find on the tower site was the 36 × 34 cm large and 0.08 meter thick fragment of the building inscription, which was recovered from the rubble on the south side of the watchtower in 1906.

The missing text passages on the right-hand side of the “irregular and rather fleeting” inscription carved into a spring tuff plate could be supplemented as follows with the help of the building inscription of the Etzgen-Rote Waag watchtower that was created at the same time :

Salvi [sd (ominis) n (ostris)]
Valenti [niano]
Valente e [t Gratiano]
per (petuis) tr (iumphatoribus) senp [er Augg (ustis) in]
summa rapida [burgum]
fecit sub cura [- - - ]
consul (ibus) d (omino) n (ostro) Gratian [o II et Probo v (iro) c (larissimo)]

Translation according to Schulthess: «During the happy reign of our Lords Valentinianus, Valens and Gratianus, the constant triumphators and always illustrious emperors, he built [this watchtower] on the upper rapids, under the direction of ..., in the year that our Herr Gratianus for the second time and His Excellency Probus were consuls. "

Thanks to the naming of emperors Valentinian I (364–375), Valens (364–378) and Gratian (367–383), the building inscription can be dated to the period between 367 and 375 AD. The date can be narrowed down even more precisely if one assumes that the tower - like that of Etzgen-Rote Waag - was commissioned during the 2nd consulate of Gratian and his fellow consul, Probus. The latter must be the Sextus Claudius Petronius Probus (330 / 340–389) - also mentioned in Ammianus Marcellinus ( Res gestae 27,11). According to the fasti consulares , he was consul with Gratian in 371. In the consular dates he is called either only Probus or Petronius Probus for reasons of space, Gratian also bore the title Augustus , as on the inscription from Etzgen. The building inscription is now in the Swiss National Museum in Zurich .

Watchtower

One of the reliefs on the Trajan's Column in Rome (113 AD) shows watchtowers (turres) on the lower Danube, next to them hay or straw stacks, presumably to feed the beasts of burden, and a pile of wood for fire signals. There is also a torch attached to each tower, which was almost certainly used to transmit messages. The late antique towers on the Rhine could have looked something similar.

The tower - or burgus - has a rectangular floor plan, slightly shifted to SE, measuring 8 meters (outside) x 4.8 meters (inside). The rising is still 1.9 to 2.4 meters high. A 0.1 x 0.2 meter, slightly pink plaster residue in the corner between the north and east walls suggests that at least the inside of the watchtower was plastered. It was partially protected by a wall and a ditch as obstacles to approach. The defensive moat, around 1.1 meters deep and 2 meters wide, is around 8.5 meters, the wall around 5 meters from the watchtower. Red discolouration that can be seen at specific points on the lowest stone layers of the wall shells is due to a great deal of heat. This suggests that he fell victim to a fire. This is also evidenced by a - unfortunately undated - layer of fire that was cut "just a little below the surface" at the beginning of the 20th century. The profiles of the two exploratory cuts examined in the 1930s show that this 0.2 to 0.3 meter thick layer of fire could also be detected 4 meters away from the watchtower. The western exploratory cut revealed that the fire layer is covered by rubble. The latter was viewed by Karl Stehlin as "rubble from the demolition of the wall". I.e. It consisted mainly of mortar, so there were obviously no larger stones in it - at least on the edge of the rubble hill. This is probably due to medieval stone robbery for repairs to the south wall. The rubble hill, which was only removed in 1932/1933, could also speak for a medieval re-use. The location would also be extremely convenient for building a moth .

Walls: They consist mainly of limestone, which probably comes from the nearby banks of the Rhine. Their strength varies between 1.5 and 1.6 meters. The opus caementitium of the wall core and part of the ancient wall shells have also been preserved. The wall formwork consists of evenly prepared hand blocks made of Malmkalk. Occasionally there are also some made of spring tuff and reed sandstone in the masonry. In the outer shell of the south wall there is a 2.8 meter long layer of upright or sloping bricks. They can also be seen in the photos that were taken after Jakob Heierli's excavations in 1922. The latter prove that it is not a question of a selective repair of the outer wall shell, but rather a subsequent bricking up. Such was also recognizable on the inner shell of the south wall, where the lower third consists of hand blocks, in the upper third of larger, partly upright limestone stones, possibly an indication of a medieval use of the building.

Scaffolding holes: The cavities (diameter 0.1 meters) in the wall core recorded on the older plans are scaffolding lever holes. As the views of the western wall show, they lie around 1.7 meters above the protrusion of the foundation. The remaining holes were no longer visible in 2014 because the top of the wall was covered with a leveling layer of lean concrete and the cavities in the wall shells were also sealed with Portland cement and stone chips.

Door opening: The threshold of the entrance door in the north wall consists of - formerly - three limestone blocks. The smaller of the two swell stones consists of a greenish, porous limestone (= shell sandstone from the Tertiary ) and was apparently already split into two parts at the time of its exposure. The smaller fragment is lost today. The larger, western swellstone consists of a yellowish, very fine limestone (= Rauracien limestone?). The door hinge and swivel pan are also relatively well preserved. The grinding marks caused by the closing and opening of the wooden door were still visible on it.

Foundation: The lower edge of the tower foundation rests on the limestone. But this only applies to the western wall. The other foundations rest on patio gravel. According to Jakob Heierli, the protrusion of the foundation was 0.1 meters wide and is said to have been visible on both the inside and the outside of the wall. The latter can also be seen on the findings plan published by Karl Stehlin. During the renovation in 2014, it was recognized that the protrusion of the foundation was up to 0.2 meters wide in places, but in some parts also ran in line with the lowest stone layer of the rising. This shows that the ancient excavation was obviously not marked out very precisely and that the alignment of the rising was only determined after the foundation was built. Observations at the transition to the rising further showed that the foundation consists of a very resistant opus caementitium . It had also been mixed up with smaller and larger limestone stones and brick splinters.

garrison

It is conceivable, but not proven, that the watchtower was built by members of the Octavani ( Legio VIII Augusta ) stationed in Argentorate ( Strasbourg ) . This Legio palatinae belonged to the field army ( Comitatenses ) in late antiquity and was under the command of the Comes tractus Argentoratensis .

Protection provisions

The area has been designated as the “Kadelburger Lauffen-Wutach estuary” with 38.5 hectares since March 9, 1993, as a nature reserve with the number 3.192. The Kadelburger Lauffen is also part of the 269.4 hectare FFH area Hochrhein east Waldshut . The ground monument is protected in accordance with the Federal Act of June 20, 2014 on the Protection of Cultural Property in the Event of Armed Conflict. Climbing the ruin, starting a fire, damaging the masonry and tampering with the ground are prohibited by law. No liability is accepted in the event of an accident.

See also

List of forts in the Danube-Iller-Rhein-Limes

literature

• Matthäus Merian: Topographia Helvetiae, Rhaetiae et Valesiae. C. Dankers, Amsterdam 1644.
• Ferdinand Keller: The Roman waiting areas, speculae, along the left bank of the Rhine from Lake Constance to Basel. In: Anzeiger für Swiss Archeology. No. 1, 1869-1871, pp. 237-248.
• Jakob Heierli : The Roman observatory during a little run in Koblenz. In: Anzeiger für Swiss Archeology. No. 9, 1907, pp. 186-189.
• Otto Schulthess: The inscription of the Roman observatory at Kleiner Laufen near Koblenz. In: Anzeiger für Swiss Archeology. No. 9, 1907, pp. 190-197.
• Felix Staehelin: Switzerland in Roman times. Schnyder v. Wartensee, Basel 1948.
• Karl Stehlin, Victorine von Gonzenbach: The late Roman watchtowers on the Rhine from Basel to Lake Constance. 1. Lower route: from Basel to Zurzach. Institute for Prehistory and Protohistory in Switzerland, Basel 1957.
• Rudolf Degen: Late Roman fortifications on the Rhine: Weiach, Koblenz and Zurzach. In: Helvetia archaeologica. No. 1, 1970/1972, pp. 41-49.
• Gerold Walser: Roman inscriptions in Switzerland. Part II: Northwest and North Switzerland. Bern 1980.
• Walter Drack : The late Roman border weir on the Upper Rhine. In: Archaeological Guide of Switzerland. No. 13, second, revised edition with reference to older literature, Basel 1993.
• Peter-A. Schwarz: New research on the Late Antique Upper Rhine Limes in the canton of Aargau I. The watchtowers Koblenz-Kleiner Laufen, Möhlin-Fahrgraben and Möhlin-Untere weirs. With contributions by Sandra Ammann, Sabine Deschler-Erb, Juha Fankhauser, Lukas Freitag, Simon Jeanloz, Tina Lander and Daniel Schuhmann. Pp. 44-54 (PDF; 6.39 MB).
• Martin Hartmann, Hans Weber: The Romans in Aargau. Verlag Sauerländer, Aarau 1985, ISBN 3-7941-2539-8 .
• Alois W. Hassler, Alfred Hidber: History of the restoration of the Roman observatory at Koblenzer Laufen (= contributions to the history of the Zurzach district. No. 8, 2015, pp. 123–128).

Remarks

1. ↑ cf. Watchtower Möhlin-Fahrgraben , watchtower Möhlin-Untere Wehren
2. ↑ CIL 13, 11537
3. ↑ CIL 13, 11538
4. ↑ Notitia Dignitatum occ. XXVII

Web links

Location of the watchtower on Vici.org