Burgplatz (Duisburg)

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Burgplatz
City coat of arms of the city of Duisburg.svg
Place in Duisburg
Burgplatz
Town hall and Salvatorkirche on Burgplatz
Basic data
place Duisburg
District Old town
Hist. Names de Borcht
Confluent streets Salvatorstrasse, Alter Markt, Oberstrasse, Poststrasse, Gutenbergstrasse, Schwanenstrasse, Am Rathausbogen
Buildings Salvatorkirche , Duisburg Town Hall, Carmel Church, Old Post Office, Nuremberg House
use
User groups Pedestrian traffic , parking spaces
Technical specifications
Square area approx. 5000 m²

The Castle Square in Duisburg is the nucleus of the city of Duisburg. Today, the square is a semi-open space, limited only by the Duisburg town hall and part of the Salvatorkirche .

investment

Until it was destroyed in World War II , the square was surrounded by residential buildings. Today the old location of the churchyard of the Salvatorkirche (until 1821) is included in the area of ​​the Burgplatz. Until 1900, with the construction of the new Duisburg town hall, the churchyard was separated from the actual Burgplatz by the street known as "Graat".

After the Second World War, this area was designated as a green area. Today the square is bordered by Schwanenstrasse in the south and Poststrasse in the east.

The Burgplatz covers about 5000 square meters, each about 70 meters in length and width. Geophysically it is the northern branch of the Bergisch low terrace . In Roman times it was located directly on the Rhine , only a few hundred meters from the confluence with the Ruhr. Located about eight meters above the banks of the Rhine, the area was used to secure the Rhine crossing on Hellweg . A building for border security was already located here in Roman times.

Early history

In the late Merovingian Chronicle, the Liber Historiae Francorum , it is reported that Chlodio , the King of the Sal Franks, had his ruling seat in a fort called Dispargum . From there he crossed the Rhine with his army , killed the Roman population and drove them out.

Territory of the conquests of Chlodio in the 5th century

According to the German historian and archaeologist Joseph Milz , based on this source and other sources from the 8th to the 12th century, this dispargum can only be today's German Duisburg, where the castle of Chlodio was located.

Burgplatz in Duisburg based on the layout of the original map from 1823 to 1825

This fort was located on the site of today's town hall and today's Burgplatz and can be traced back to a Roman complex on the castle hill on the Rhine, on which the Duisburg royal palace was built in the 9th century . Royal Palaces were considered to be the ruler's temporary residences , who used them on his travels through his empire.

With a record of Regino , abbot of the Prüm monastery in the year 883/884, who mentions Duisburg in connection with the Normans' campaigns in the 9th century, there is the first clearly dated mention of the vernacular name Duisburg:

Eodem anno Normanni, qui in Chinheim ex Denimarca venerant, adsentiente Godefriedo Rhenum navigio ascendunt et Diusburh oppido occupato ammunitionem in eodem loco more solito construunt et in eo toa hieme resident

(Translation: This year the Normans came from Denmark to Kenemerland, with Gottfried's consent, by ship up the Rhine after they had occupied the place Duisburg and built a fortification of their kind at this place and stayed there all winter.)

The Burgplatz with the royal court that was built in the 8th century was probably already a fortified place with residential houses, as the name oppidum indicates. Next to the royal court, the Palatinate Church, consecrated to Saint Salvator , the “Grote Kerk” was built in the 9th century .

In the 10th century the royal court was expanded into a royal palace. A few events point to the importance of Duisburg at that time: for example, an imperial synod under Heinrich I took place in 929 . In 944 there is a report from a state parliament under Otto I in Duisburg. In 1002, Henry II had the Archbishops of Cologne , Liège and Cambrai meet in Duisburg to convince themselves of their loyalty to him on the occasion of his election as a king . Between 929 and 1129 a total of 17 royal and imperial stays in Duisburg are documented.

Already before the year 1000 the shifting of the Rhine became apparent. It turns away from Burgplatz about 2500 m west. However, the ships no longer had to anchor in the river, but could moor in the calm fairway of the old Rhine arm .

At the beginning of the 12th century, Duisburg was one of the places that opposed the Archbishop of Cologne and stood on the side of Emperor Heinrich V , and was referred to as regia villa and not yet as a city . Vogt lords of the villa were the dukes of Limburg. They administered the city on behalf of the emperor. At the beginning of the 12th century, a dispute arose between the Duisburgers and the Vogt over the rights of use in the Duisburg Forest .

Finally, King Lothar III confirmed . in a document from 1129, "that the bottom of the forest belongs to the royal villa Duisburg, and that the Duisburg citizens (cives) can break stones according to their needs". In the period that followed, there was lively construction activity around Burgplatz.

In 1165, Emperor Friedrich Barbarossa set up biweekly cloth fairs in Duisburg for Flemish merchants, which were transferred to Frankfurt am Main in the 14th century .

At first the area of ​​the royal palace was called “ super castrum ”, from the middle of the 14th century “ op der Borgh ”, which was popularly known as “ op der Burg ” until before the Second World War, Johannes Corputius called the area afterwards named him plan of the medieval city as " de Borcht ".

Late Middle Ages

At the beginning of the 13th century, the Schola Duisburgensis , one of the oldest schools in Germany, was built on Salvatorkirchhof / Flachsmarkt, the forerunner of today's Landfermann-Gymnasium .

After the expansion of the Palatinate in Kaiserswerth in the middle of the 13th century, the Duisburg Palatinate lost its importance. The Teutonic Order acquired the buildings of the Pfalzanlage and took over the patronage of the church.

The Corputius plan from 1566 shows Duisburg with the Burgplatz according to exact geographic measurements.

In 1283 the buildings of the Palatinate and the adjacent Salvatorkirche fell victim to a fire, which almost completely destroyed the entire complex. The Vogt of Limburg donated a castle-like complex to the Minorites , which the monastery brothers expanded into a monastery, hospital and church. The construction site of the Friars Minor also fell victim to the city fire. The rebuilt Church of the Minorites with its blue roof is clearly visible on the plan of Corputius.

After the fire, the walls of the Palatinate were still standing, so that smaller houses were added to them towards Burgplatz and to the northwestern Pfeffergasse. The former interior of the Palatinate was used as a building yard for a long time . These walls can still be seen on the Corputius map .

In 1290, the then imperial city of Duisburg was pledged to King Rudolf von Habsburg in 1290 against 2000  silver marks as dowry to Count Dietrich von Kleve and thus lost its independence from the empire.

At the end of the 13th century, the Teutonic Order built a new church. The foundation stone of today's church was probably laid in 1316.

After the flood of the millennium in 1342, also known as the Magdalene flood, Duisburg developed more and more into an agricultural town .

In the middle of the 14th century, the citizens of the city built a domus consulum (mayor's house), a town hall, on the site of the Palatinate, which was first mentioned in documents in 1391. This town hall was next to today's town hall arch. Its main front, however, was not oriented towards the Burgplatz, but towards the rear Weinmarkt.

In 1467 the tower of the Gothic church burned down. The tower was not restored until 1513.

The old town hall consisted of two buildings, one of which was the remains of the old palace complex, which remained almost intact during the conflagration in 1283. The building is marked with the letter "M" on the plan of Corpurtius from 1566.

To the north, the Burgplatz was bordered by the so-called Schupkuylenstraete with houses on both sides. The name refers to the punishment of "Schupfen", after which the delinquent was pushed into a water hole and submerged. In the middle of the 17th century the street was named "Graat", derived from the Latin name "gradus" for "level". The street could only be reached from Pfeffergasse via stairs. To the east the square was limited by about 10 houses, the double row of houses to the south of the square still showed the course of the castle fortifications.

Until World War II

In 1512 the old school building of the Schola Duisburgensis was demolished and a new building was erected at the Salvatorkirchhof, consisting of two floors with classrooms and a teacher's apartment in the gable.

In 1543 the city council decided that preaching was only allowed in the evangelical sense . In 1555 the Reformation in Duisburg was finally completed. The rich medieval furnishings of the Salvator Church fell victim to the Reformed Confession.

The Salvator statue is removed from the Salvator Church. Few Catholics remained in the city. The meeting place for the few Catholics was the small Minorite Church next to the large town church.

In 1552 the cartographer Gerhard Mercator moved to Duisburg and moved into a house on Oberstrasse. From 1559 to 1562 he worked as a teacher of mathematics and cosmography in the newly founded Duisburg Academic Gymnasium , today's Landfermann Gymnasium .

Around 1566 his pupil Johannes Corputius produced the fairly precise cityscape of Duisburg named after him from a bird's eye view, whereby he carried out the necessary topographical observations primarily from the tower of the Salvatorkirche. Mercator dies in 1594 and is buried in the Salvatorkirche.

In 1610, 36 representatives of the Reformed congregations in the Rhineland met in the Salvatorkirche. This synod forms the cornerstone for the Evangelical Church in the Rhineland.

In 1613, after a lightning strike, the tower of the Salvator Church burned down again. The church received a baroque tower dome in 1692. In 1719 the market of the city of Duisburg was moved from the old market to the "Burg" as a Wednesday market.

Coming from France and on the way to Munster, Johann Wolfgang von Goethe stopped in December 1792 at the inn "Zur golden Krone" on Oberstrasse. Goethe visits the philosophers Plessing and Blasius Merrem , both professors at the University of Duisburg, founded in 1655 .

The Minorite Church was extended to the west by the end of the 18th century. The new nave was given a vault instead of a wooden ceiling. In 1832 the church monastery was closed because there were no more new members for the brothers in the community. The church is taken over by the diocese of Münster . The diocese appoints a diocesan priest and the Minorite Church thus became a Catholic parish church .

In 1802 the old town hall was replaced by a building of the same size. Due to the steady growth of the population , it became necessary to expand the town hall by adding an extension in the direction of the Salvatorkirche. As a result, some houses had to give way.

Mercator fountain on Duisburg's Burgplatz
Market on the Burgplatz in front of the Salvatorkirche, around 1850

In December 1805, the French took over the regiment in Duisburg's town hall after Prussia ceded the right bank of the Duchy of Cleves to Napoleon . Napoleon himself honored the duchy and the city of Duisburg in 1811. He is said to have given the order to relocate the city's university to Düsseldorf . The French rule ended in 1813. The university was founded on October 18, 1818 on the basis of a cabinet order from Friedrich Wilhelm III. officially closed. Large parts of the Duisburg university library were relocated to the newly founded university in Bonn , where it formed the basis of the newly founded Bonn library. The university scepter of the Duisburg University also came to Bonn, where it is still available today.

In 1823 Duisburg becomes the district town of the district of Duisburg, which was newly founded from the former districts of Dinslaken and Essen . From Burgplatz, an area is now administered that includes today's large cities of the western Ruhr area Duisburg, Essen , Mülheim an der Ruhr , Oberhausen and today's southern part of the Wesel district on the right bank of the Rhine . By cabinet order of August 10, 1857, the Essen district was separated from the Duisburg district in 1859 and reorganized.

In 1873 Essen left the Essen district, and in 1874 Duisburg left the Duisburg district. Both cities are now forming their own urban districts and are preparing to become large industrial cities.

In 1878 a monument was erected on the Burgplatz for the cartographer Gerhard Mercator : a sandstone fountain in the style of historicism , which was designed by the Düsseldorf sculptor Anton Josef Reiss .

The still image Mercator on the well construction is two and a half meters high. It shows Mercator in a clothing typical of the Renaissance while he looks down at a globe at his feet .

The fountain structure consists of four round arches. Four dolphins can be seen between the pillars of the round arches, spewing water into the fountain basin. Four children's figures sit at the four corners of the structure, each of the individual figures carries a symbol in its hand: the herald's staff for trade , the cogwheel for handicrafts , the anchor for shipping and the book for science . The inscription on the four gable fields reads: "Gerhard Krämer gen. Mercator / born on March 5th, 1512 in Rupelmonde / lived and worked in Duisburg since 1552 / died in Duisburg on December 2nd, 1594".

On Christmas Eve of 1881 the horse-drawn tram drove across the Knüppelmarkt for the first time . It created a new connection between Duisburg and the neighboring city of Ruhrort . The horse-drawn tram was replaced by the electric one in 1896 .

In 1888 the tower of the town hall received an increase. This was provided with an electric clock . It soon became apparent that the town hall, built in 1802, could no longer meet the demands of the city.

In 1890 the population of the city had increased from around 5,000 in 1802 to 60,000 in the meantime, so that a completely new construction of the town hall was planned.

Construction of the new town hall began on August 25, 1897. As a result, 25 houses and land on Pfeffergasse had to give way. The “Graat” also fell victim to the new construction of the town hall. The first phase of construction of the new administration building was completed on April 1, 1900, which meant that the old town hall could be demolished.

The Burgplatz at the beginning of the 20th century with the new town hall that still exists today

During the construction of the new town hall, the Berlin Palatinate Researcher Konrad Plath tried to find evidence that Duisburg was the dispargum mentioned by Gregor von Tours with the Palatinate of the early Franconian King Chlodio on Burgplatz in Duisburg.

He discovered walls on the edge of the Burgplatz, which turned out to be remnants of the medieval royal palace. Plath never published his research, but his notes have been preserved. They formed the basis for further research in the 20th century.

On May 3, 1902, the new town hall designed by the Karlsruhe architect Friedrich Ratzel was inaugurated. The construction costs totaled 2.6 million gold marks , a third of the city's annual budget . A 4 meter high Roland figure was also placed on the northeast side .

In parallel to the new construction of the town hall, extensive renovation work was carried out on the Salvatorkirche. The baroque onion dome , which replaced the pointed tower after the lightning strike in 1613 and which could still be seen on Corputius' plan, disappeared. The church received an octagonal bell storey and a new steep top.

As a result, the entire tower reached a height of around 90 meters, but did not reach the height of the original tower from the 14th century, which measured 112 meters and which was then the tallest building in northern Germany .

The neo-Gothic Church of Our Lady was inaugurated as early as 1896 , into which the original nave of the Minorite Church was incorporated as the southern aisle. The Liebfrauenkirche offered space for almost three thousand visitors and was, next to the Salvator Church, the largest church in Duisburg. The church tower reached a height of 100 meters. The Evangelical Salvatorkirche and the Catholic Church of Our Lady were now at eye level.

In 1904 all work on Burgplatz was finished. Burgplatz and churchyard of the Salvatorkirche now formed a generous space unit. For four decades, the high towers of the new town hall, the Salvatorkirche and the Liebfrauenkirche formed an urban unit.

Burgplatz with the dominating towers of Burgplatz, 1911

On October 1, 1905, the cities of Ruhrort and Meiderich were incorporated into the city. The city's population grew to about 192,000. Life in the young city was concentrated on and around Burgplatz and the streets and alleys to the south and east of it, especially on Knüppelmarkt, Weinhausmarkt, Münzstraße, Poststraße and Beekstraße, where the department stores of Jewish fellow citizens are mainly located were to be found.

The Royal Post Office was located on Poststrasse, a building erected in 1891 in the late Gothic Renaissance style. The police prison was located on the extension of Poststrasse, Georgstrasse and the former Jorisstrasse. The old "inn" mentioned in 1316 was located on the Knüppelmarkt, which met Poststrasse to the west. The Knüppelmarkt was in the area of ​​the former castle fortifications and it was one of the most popular shopping streets in the city and was a meeting place with restaurants and cafes.

On March 15, 1920, a department of the Duisburg Resident Armed Forces, the "Kaiserberg" raid troop, moved into the town hall. On the Burgplatz in front of the walls of the town hall, the police and other units of the resident defense have posted themselves. The resident armed forces sympathize with the Kapp putschists , who led a putsch against the government under Friedrich Ebert on March 13, 1920 in Berlin under the administrative officer Wolfgang Kapp and General Walther von Lüttwitz .

As a reaction to the radical right-wing putsch, the Red Ruhr Army was formed in the Ruhr area and called for a general strike . The city government officials condemn the coup. But she refuses to comply with the demands of the trade unions and workers to disarm the resident guard. On March 16, 1920 bloody clashes broke out. The police and the resident service open fire against an action committee from the KPD and USPD .

The Kapp Putsch failed on May 17, 1920, but units of the Red Ruhr Army moved into Duisburg on March 19, leading to chaotic conditions in the city. On Holy Saturday of the year 1920, April 3rd, the uprising was suppressed by troops of the Reichswehr. The town hall was bombarded and the tower was badly damaged. The Reichswehr secured the town hall with heavy weapons. The fighting kills around 100.

Street layout around Burgplatz, 1925

On March 8, 1921, French and Belgian troops march into Duisburg. The Duisburg town hall and the Duisburg main post office are occupied. At the same time troops invade the neighboring city of Düsseldorf. The Allies are trying to enforce the London ultimatum of May 5, 1921, with which the victorious powers of World War I wanted to enforce their payment plan for German reparations against Germany. In January 1923 the entire Ruhr area is occupied. In the course of the Dawes Plan , the occupation of the Ruhr area ended in July / August 1925. The last troops left Duisburg on August 25, 1925.

Karl Jarres had been Lord Mayor of the city of Duisburg since 1914 . At the same time he held the office of Vice Chancellor and Interior Minister from November 11, 1923 to January 15, 1925 . In the 1925 presidential election Jarres received the most votes in the first ballot, but withdrew his candidacy in favor of Hindenburg in the second ballot .

After the seizure of power by the National Socialists to Jarres was forced on 16 May 1933 withdraw from the Lord Mayor. On May 16, 1933, NSDAP party member Ernst Kelter took over the office of mayor in Duisburg's town hall.

Around midnight between May 12 and 13, 1943, 572 bombers took to the air in England . Destination: Duisburg, “aiming point cathedral”. This meant the Salvatorkirche and Burgplatz. 1,085 high-explosive bombs, 106 air mines, 112,700 incendiary bombs and 15,275 phosphorus incendiary bombs turned the city into a sea of ​​flames. A total of 1,599 tons of bombs were dropped within 45 minutes . Between 1:52 and 2:55 a.m. that night, the medieval old town of Duisburg went under. According to the British Air Force, the attack was the heaviest attack on a German city to date.

reconstruction

The Burgplatz, like the entire old town of Duisburg, changed its appearance in a radical way after the Second World War.

The bombs of the war destroyed the spire and the roof of the town hall. The town hall was rebuilt in simpler forms. He got a new tip. The front gable above the entrance and the helmet of the town hall tower were not rebuilt. Now that it sank into ruins for the fourth time, the pointed helmet of the Salvator Church was no longer replaced. Anyone who tries to recognize the old city with the old Corputius plan will have trouble finding old streets or guessing the location of the castle.

After 1945, the Schwanenstrasse , which came from the direction of Ruhrort and previously led to the Alter Markt, was widened and connected directly to Poststrasse. As a result, the war-damaged buildings and old streets to the south and south-west of the Burgplatz and at the Salvatorkirchhof disappeared: Weinhausmarkt, Knüppelgasse, Holzgasse, Holzstrasse, Trankgasse and Knüppelmarkt. To the east of Burgplatz, Georgsgasse disappeared due to the widening and lengthening of Poststrasse and the demolition of the houses without replacement .

Roman Catholic Carmel Church in Duisburg

By the end of the 1950s, all of the buildings that surrounded the square, next to the town hall and Salvator Church, had disappeared. The last building that gave way to the demolition excavator was a residential building that housed the “Wilhelm Mues” restaurant in the basement. From Burgplatz there was now a clear view of Poststrasse with the Alte Post, which survived the war almost hopelessly, and of Schwanenstrasse.

Plans to loosen up the narrow Duisburg city ​​center around Burgplatz existed as early as 1939. However, these were not tackled when the war began. In the 1960s it was noticed that Burgplatz was isolated from the rest of the city center as a result of the post-war restructuring measures and that this became a problem that has not yet been resolved.

At the suggestion of Bishop Franz Hengsbach, the new single-nave Carmel Church was built on the site of the former Minorite Church, which was destroyed in the war .

The new Liebfrauenkirche was built in 1960 at a new location on König-Heinrich-Platz in the immediate vicinity of the regional court as a two-story reinforced concrete building in the brutalist architectural style .

In 1964, a pedestrian passage was created between Burgplatz / Schwanenstrasse and Kuhstrasse. The 2,300 square meter tunnel area was reached via seven stairs / escalator entrances. Shops, shop windows and showcases created another shopping area in downtown Duisburg. This became necessary because the "Kuhstrasse breakthrough" occurred at the convergence of Schwanenstrasse, Poststrasse and Kuhstrasse, which created a new major traffic junction in the city center. These measures, however, further isolated the Burgplatz from the city center.

Reconstruction of the outlines of the halls on the old market and town hall

Urban archeology

In the destroyed Duisburg, Fritz Tischler resumed Konrad Plath's archaeological research after the war. From 1938 he worked as a scientific assistant and head of the prehistoric department of the Lower Rhine Museum in Duisburg. From 1950 until his death in 1967 he was director of the museum.

Carpenters dealt intensively with the Burgplatz, the medieval palace complex and the city wall that was 80% preserved at that time. Günther Binding published Tischler's research after his untimely death.

With the construction of the underground tram in the 1980s, the opportunity arose to carry out further excavation investigations. City archives director and historian Milz discovered the remains of the outer walls of the Palatinate district in the summer of 1980. However, he found no so-called cultural layers on Burgplatz , which he attributed to erosion and war damage.

In contrast, well-preserved cultural layers were discovered at the rear of the Old Market in the area of ​​the Roman bed of the Rhine and the later medieval floodplain, which reached back into Roman times. In December 1990 the inauguration of the archaeological zone Alter Markt took place, which bears testimony to the approximately 2000-year history of a city which, according to the excavation results, dates back to the 1st century AD.

Urban archeology has been neglected for financial as well as ideological reasons since the 1990s, which led to fierce controversy. Urban archeology is now leading a shadowy existence in the city.

Today's Burgplatz as a place of social life

In 1945 the US military government replaced the city ​​treasurer Hermann Freytag , who was appointed by the NSDAP regime as head of an "emergency authority" for the city administration during the war years, with the lawyer Dr. Heinrich Weitz and entrusted him with the office of Lord Mayor.

Castle Square with City Hall and Salvatorkirche from the inner harbor seen from

On November 9, 1948, the 42-year-old August Seeling was elected as Germany's youngest mayor. He held the office until 1969, making him the longest-serving Lord Mayor in Germany. On May 25, 1965, he received Queen Elisabeth of England with Prince Philip as part of her first trip to Germany after the war in the Duisburg City Hall, where the Queen signed her name in the city's Golden Book , roughly at the point where it was over a thousand years ago the main hall of the Duisburg royal palace stood.

On October 18, 1949, the first market day after the war took place on Burgplatz in the shadow of the Mercator fountain, until the last market day was held in 1972. The Burgplatz disappeared more and more from the consciousness of the Duisburg population as a historically significant place.

Today the square is primarily used as a parking lot. Burgplatz and the old town are no longer identified by the population as the central district of Duisburg. Instead, it has moved in the direction of Königstrasse , König-Heinrich-Platz and the main train station .

literature

  • Heinrich Averdunk: On the history of Duisburg, in particular the Burgplatz and town hall . In: Festschrift for the inauguration of the new town hall building of the city of Duisburg am Rhein on May 3, 1902 . Steinkamp, ​​Duisburg May 3, 1902, p. 7–30 ( digitized , PW Metzler Verlag, Duisburg 2017).

Individual evidence

  1. ^ Joseph Milz, Günter von Roden: Duisburg in the year 1566 (=  Duisburger Forschungen . Volume 40 ).
  2. ^ Joseph Milz: History of the City of Duisburg . Mercator-Verlag, Duisburg 2013, p. 28-29 .
  3. ^ Archbishop of Cologne I. (Ed.): Regesten 1954–1961 . No. 324 .
  4. ^ Per Johann Steininger: History of the Trevirer under Roman rule . Verlag der Lintzschen Buchhandlung, Trier 1845.
  5. ^ Joseph Milz: Duisburg - Pictures tell stories . Mercator-Verlag, Duisburg 1983, p. 42 .
  6. ^ Joseph Milz: History of the City of Duisburg . Mercator-Verlag, Duisburg 2013.
  7. Gerd Brouwer: Duisburg - yesterday and today . Ed .: Gert Wohlfarth. Mercator-Verlag, Duisburg, Munich 1969, p. 9 .
  8. Duisburg Roland
  9. Duisburg - The old city . Sutton-Verlag, Erfurt 1997.
  10. Klaus-Dieter Vinschen: A Short History of the City of Duisburg - World War and Weimar Republic . Walter Braun Verlag, Duisburg 1996.
  11. The old town of Duisburg died 70 years ago. In: Lokalkompass Duisburg. May 13, 2013, accessed April 21, 2016 .
  12. ^ Culture and City History Museum of the City of Duisburg (ed.): Bombs on Duisburg . Verlag Fachtechnik + Mercator-Verlag, Duisburg 2004.
  13. ^ Binding: Archaeological-historical investigations into the early history of Duisburg . Duisburg 1969.

Coordinates: 51 ° 26 ′ 7.4 "  N , 6 ° 45 ′ 42"  E