Hohentweil is a huge castle and fortification located just west of the Bodensee (Lake Constance), above the town of Singen. The view is incredible... when the weather is cooperating. In 1979, it was not, as I was in the process of cycling to Switzerland and had just emerged from a day and a half of continuous rain. But the weather was great in 2005, and the photos fantastic.
Below, two views from Hohentwiel to Hohenkrahen, which was another castle in the region and now largely in ruins. On the right, in 1979, and on the left in 2005. Note the new Autobahn that runs diagonally in the new photo.
Hohentweil was built atop a volcanic plug, which is a geological formation created by the rapid cooling of magma within a volcanic cone, followed by the erosion of the ash surrounding it. This leaves a protrusion of granite, much like Hohenkrahen above. Devil's Tower in the United States is an example of a volcanic plug. The illustration at top shows Hohentwiel under siege in 1641 during the Thirty Years War. This shows how the castle was placed on the plug.
The castle was first mentioned in records in 806 when it was held by Pippin, the son of Charlemagne. By the 1080s, it was held by Ulrich von Eppstein, after which it changed hands numerous times. By the early 1500s it was held by the Duke of Wurttemberg. The castle came under five sieges during a ten-year period of the Thirty Years War. At that time, it was under the local command of Konrad Wiederhold, who refused to surrender to repeated attempts by the imperial forces of the Holy Roman Empire to seize it. Later, he exercised his own initiative and swept down on the town of Uberlingen below to capture it and claim it for the Swedes. However, the castle was unable to hold out against the French, commanded by General Vandamme, in 1800, and after five months was finally blown up. By the late 1960s, serious excavation work began on the ruins, and continues to this day. When I first saw these ruins in 1979, it was heavily overgrown. Today, some of this vegetation has been cleared, and more of the ruins are visible.
To get to the castle, take the Autobahn to Singen. As you approach you will see signs to the castle. There is ample parking below, and an enjoyable walk to the top. Above left, the view of the castle, barely visible, atop the volcanic rock. Left, the entrance... a long series of tunnels into the mountain. Below, a higher view of the tunnel showing one of the walls.
