In 2001 the Jungfrau-Aletsch region was labelled World Natural Heritage by UNESCO. The Heritage Site stands for the splendid natural beauty of the Alps. At its heart lies the impressive Eiger, Mönch and Jungfrau rock massif and the glacial landscape surrounding the Great Aletsch Glacier. On the southern slopes of the Bietschhorn, this high-alpine scenery is gradually transformed into a submediterranean rocky steppe. The Aletsch Glacier is the biggest glacier in the Alps, with a length of 23 km. The fascinating world of snow and ice can be experienced on a guided tour or from the Jungfraujoch. The climatic conditions on the southern slopes lend the landscape a Mediterranean touch. The Lötschen, Joli, Bietsch, Baltschieder and Gredetsch valleys have largely been able to preserve their original character. Off the beaten tracks of the main tourist routes, they offer peace and tranquillity along the bisses and mountain streams.