The steep phonolite conical hill Klíč is one of the most dominant and distinctive features of the Lusatian Mountains. In clear weather you can see as far as the Jizera Mountains and the Krkonoše. The southwest side of the mountain is broken by a 60-m-high, occasionally overhanging rock wall, on which massive icefalls form in the winter. Klíč is accessible only on foot, all year round.
Height above sea level: 760 m