Visible from 12 mi (20 km), the Haut-Koenigsbourg castle is one of the most impressive fortresses in Europe. Its construction begins in 1147 in a typical mountains castles' style. It can indeed only be crossed by the drawbridge which spans the moat between the fortress and the main castle. The south house, well exposed and including a chapel, is reserved for the lord and his family. The north house, colder, serves to welcome guests. To the east, the keep rises above the plain at 203 ft (62 m). Symbol of the lord's power, it is also the last refuge in the event of an attack. The walls are 6,5 ft thick (2 m), and twelve arrow slits are used to harass the attackers.