The Haut-Koenigsbourg keep, square in shape, is 203 ft high (62 m) and is the highest in Alsace. To reach its entrance, a spiral staircase leads through the two floors of the seigniorial home. A secret door allows access to the dungeon, which has four levels. The climb to the top is carried out within the keep's walls, by narrow and dark stairs. From the windows of the summit room, the 360° view plunges over the plain, the valleys, and the mountains. On a clear day, it is also possible to glimpse the snow-capped summits of the Alps.