For centuries, trachyte, latite and basalt have been mined for in the Siebengebirge. The quarries almost destroyed our region. Hardly anything has remained of Mount Stenzelberg, which today is an abandoned quarry. The same goes for Mount Weilberg, an abandoned quarry as well, and also a natural monument where you can see …
Trachyte from Mount Drachenfels
Already the Romans mined for trachyte at Mount Drachenfels. In Bonn and Cologne, and even in Xanten and Nijmegen, trachyte from Drachenfels was used.
In the Late Middle Ages, large parts of Cologne Cathedral were built with trachyte from the Drachenfels. The burgraves became rich, but the Cathedral was not finished.
In 1823, repair work began on Cologne Cathedral. The Cathedral masonry wanted trachyte from the Drachenfels again, and the local stonemasons from Königswinter stonemasons wanted to do business with them right away. Many people, however, locals, Prussian officials and even the crown prince, wanted to protect Mount Drachenfels and the medieval castle ruin. Years of embittered confrontations in the media and in court followed. In 1829, the Prussian Ministry of the Interior ordered the suspension of all quarrying, but the confrontations continued until 1836, when the Prussian state bought the mountain top.
Latite from Stenzelberg and Wolkenburg
When the monks of Heisterbach Abbey started building their abbey church in the High Middle Ages, they mined for latite from the nearby Stenzelberg.
In early modern times, Mount Wolkenburg was also used as a quarry. The medieval had fallen apart, and the fine latite was perfect for the fronts of representative Baroque and Rococo buildings, so ambitious stonemasons asked for it.
Latite from Mount Wolkenburg was used at numerous very fine addresses all around Bonn, capital of the electorate of Cologne, including Bonn’s town hall, Poppelsdorf Castle, and in the Prince-Elector’s castles Augustusburg and Falkenlust at Brühl. In Königswinter, Wolkenburg latite was used for the Siebengebirgsmuseum Königswinter, Haus Rebstock in Hauptstraße, the St. Remigius church and at the wine fountain in front of the town hall, Drachenfelsstraße. Many of the way crosses along the Petersberg Bittweg are made of latite. Some older crosses have a base made of trachyte.
Basalt mining – huge quarries in the Siebengebirge
Things got even worse in the 19th and early 20th centuries, when basalt was needed for the construction of roads and, somewhat later, railway lines. At the mountains Weilberg, Petersberg and Ölberg in the Siebengebirge large quarries were opened. The Rhine front in neighboring village Oberkassel was devastated.
Finally, the damage to nature alarmed many people. Associations for the protection of the Siebengebirge were founded, which later merged to form the Verein zur Verschönerung des Siebengebirges (VVS).
On the way to the top of Mount Ölberg, you will pass a viewpoint called Humbroich-Platz. From here, you have a wonderful view across the Rhine valley. This place honors Justizrat (an honorary title bestowed by the Prussian legal authorities) Humbroich from Bonn, a devoted nature conservationist. Without him and his “Verein zur Rettung des Siebengebirges” many beautiful places in the Siebengebirge would have been destroyed forever. He has rendered an outstanding service to Mount Petersberg.
Oberpräsident von Nasse
The Prussian Minister of Agriculture, von Hammerstein, also sided with the nature conservationists, and above all the Oberpräsident (the supreme representative of the Prussian crown) of the Prussian Rhine Province back then, Berthold von Nasse. He only approved new railway lines in our region if they did not endanger the Siebengebirge, and not at all those for the transport of stones. And without a favorable connection to the railway network to transport the stones, a quarry would not pay off. The Oberpräsident even organized the boycott against basalt from the Siebengebirge, and many city along the Rhine joined in. They had roads and pathways built and were influential clients.
The Nasseplatz, an open quarry just below Margarethenhöhe, is named after him. Today it is also a popular barbecue site, but since 2015 it has been closed – due to falling rocks.
A lottery for the Siebengebirge
Back then there were no nature conservation laws with possible sanctions. The only option was to buy out as much land and existing quarries in the Siebengebirge as possible and then close them. This required a lot of money, and in the worst case a right to dispossess quarry owners. In 1897, the VVS requested a lottery to get money and the right to dispossess from the Prussian authorities.
Now there was a conflict of interests: the protection of nature stood not only against the interests of the owners of the quarries, but also against those of the quarrymen. We also have to think of those indirectly affected, like the Heisterbach Talbahn railway who mainly did freight traffic from the quarries to the factories. Finally tourism became important, too, since many people had discovered the Seven Mountains for trips, and their money supported the hotels, restaurants and public transportation.
Finally, in March 1899, Oberpräsident von Nasse could inform the VVS about the favorable decision: His Majesty Kaiser Wilhelm II had approved a money lottery with a net profit of 1,500,000 Marks for the preservation of the Siebengebirge and also granted the right to dispossess. One year later enough money had been collected to buy out wide areas in the Siebengebirge and to close down numerous quarries.
After long negotiations, purchase of land and legal disputes, the last quarry on Petersberg was closed in April 1908. But at other mountains in the Siebengebirge the quarries continued, for example at Weilberg and Stenzelberg, of which not much has remained.