Königstein Fortress, Saxon Switzerland, Germany

Königstein Fortress, one of the largest mountain fortresses in Europe, rises high in the Elbe Sandstone Mountains of Saxon Switzerland.

The 'Burgrave Gebhard vom Stein' is first mentioned in a document of King Wenceslas I of Bohemia in 1233, presumably referring to Königstein.

At that time the area belonged to the Kingdom of Bohemia.

In the 16th century, the castle underwent significant expansion to become a Saxon state fortress, with the start of construction of the imposing 152.5-metre-deep castle well between 1566 and 1569 being an important milestone.

It is still one of the deepest historic wells in Germany.