Königstein Fortress (German: Festung Königstein), the "Saxon Bastille", is a hilltop fortress near Dresden, in Saxon Switzerland, Germany, above the town of Königstein on the left bank of the River Elbe. It is one of the largest hilltop fortifications in Europe and sits atop the table hill of the same name.
The 9.5 hectare rock plateau rises 240 metres above the Elbe and has over 50 buildings, some over 400 years old, that bear witness to the military and civilian life in the fortress. The rampart run of the fortress is 1,800 metres long with walls up to 42 metres high and steep sandstone faces. In the centre of the site is a 152.5 metre deep well, which is the deepest in Saxony and second deepest well in Europe.
The fortress, which for centuries was used as a state prison, is still intact and is now one of Saxony's foremost tourist attractions, with 700,000 visitors per year.
By far the oldest written record of a castle on the Königstein is found in a deed by King Wenceslas I of Bohemia dating to the year 1233, in which a witness is named as "Burgrave Gebhard of Stein". At that time the region was split between the Kingdom of Bohemia and the Bishopric of Meissen. The medieval castle belonged to the Kingdom of Bohemia. Its first full description as Königstein ("King's Rock") occurred in the Upper Lusatian Border Charter (Oberlausitzer Grenzurkunde) of 1241, that Wenceslas I "in lapide regis" (Lat.: at the rock of the king) sealed. In this charter the demarcation of the border between the Slavic Gauen of Milska (Upper Lusatia), Nisani (Meißen Depression) and Dacena (Tetschen region) was laid down. Because the Königstein lay left of the Elbe, it was independent of the 3 aforementioned Gauen.