The Zittau mountains, where limestone peaks are juxtaposed with extinct volcanoes, extend for approximately 20km, forming a steep barrier which overlooks the Zittau basin. This region, popular with climbers and skiers, is also renowned for its thermal spa resorts, such as Lückendorf, Oybin and Jonsdorf, which make good starting points for numerous walks. The highest peaks, Lausche (793m), Hochwald and Jonsberg consist of phonolite, which forms steep cones dotted on the sandstone hills.