Top 10 Lakes in Siebengebirge

The name is once again misleading: Of course, the local hiker knows that there are by no means several lakes visible from this spot. Rather, it is the "good old Father Rhine," which can be seen several times, seen here from above.

A narrow path leads around the Dornheckensee. Great!

The path along Dornheckensee is part of the path plan, but the trail that deviates from the path is not part of the path plan. 2 years ago there were lots of signs there. Today I didn't even see the prohibition signs anymore.

The Weilberg is one of the many relics of the Siebengebirge from the time of the volcanoes that formed the landscape around 30 million years ago (Tertiary period). At that time, the volcanic activity began with a huge ash rain. Inside the earth was a huge magma focus that had created eruptions in various chimneys and crevices. Loose material was thrown explosively through these eruption sites to the earth's surface. This was deposited on the earth's surface and solidified into tuff. Lava penetrated the forming trachytuff layer and colored the tuff red at the contact zone. This can still be clearly seen today. The lava solidified into hexagonal basalt columns, often into slender columns. Later, liquid basalt penetrated the old tufa layer again in one passage and formed a "basalt tulip" at the upper end. Over the course of time, the destructive power of nature eroded the soft tuff layer through erosion, weathering and erosion. The hard layers of basalt resisted these forces and are therefore so close to the surface today that they were quarried. There are three large groups of volcanic rock in the Siebengebirge: 1. Trachyte (e.g. Drachenfels, Lohrberg) - used in the construction of Cologne Cathedral 2. Latite (e.g. Stenzelberg, Wolkenburg) - used for baroque building decoration 3. Basalts (e.g. Weilberg, Ölberg, Petersberg) - use e.g. B. for coastal reinforcement or as gravel for road and railway construction In the 19th and early 20th century, basalt was mined on the Weilberg, as in many other places in the Siebengebirge. The workers toiled for ten hours to extract the valuable stone by hand with hammers, crowbars, iron wedges or stone forks. It was particularly dangerous for the workers, who were lowered to the blast site on a rope. The extracted rock was transported to the nearby stone crushing plant. The workers loaded the mined rock into wagons and brought it down to the valley. From 1889, a narrow-gauge railway was built for transport, which led down into the Rhine Valley to the loading point on the ships. At weekends, she brought the day trippers to the Siebengebirge in passenger transport. Basalt was and is very popular for building roads, paths and railways, but also for bank and dike reinforcements (also in the Netherlands!). This quarry activity, which ended in 1942, offers the visitor a fantastic insight into times long past. Information boards give the visitor important information about the history of the origins of the volcanic landscape and the Weilberg, but also about the history of quarrying.

This is the closed Weilberg basalt quarry.

"After the completion of the Oberkassel/Ramersdorf basalt quarrying in the 19th century, some of the quarrying sites, which were up to 70 meters deep, filled up with groundwater. Embedded in steep terrain, the blue lake today offers a beautiful panorama. Signs indicate that swimming is prohibited here. Rock crumbles off the steep walls of the Ennert and falls into the lake. A dangerous undercurrent can be very dangerous for the inexperienced swimmer. Today the area around the Blue Lake is part of the Siebengebirge fauna-flora-habitat area and is subject to strict supervision." https://www.seen.de/blauer-see-bonn-oberkassel/

Especially beautiful now in the spring, because everything is blooming, green and a clear view in the forest...

The "two rangers" are only out and about in the Rhein-Sieg district, not here. I've met them there before.