The Lhasa tourist area includes Lhasa, Yangbajain, Damxung, Gyangze, Zetang, Xigaze and Yamzhoyum Co Lake. Lhasa itself is not only Tibet's political, economic, cultural and transportation center, but also the center of Tibetan Buddhism. Major tourist sites include the Jokhang Temple, Ramoche Temple, Potala Palace, Barkhor Bazaar, Norbulingka Palace and three great monasteries of Ganden, Drepung and Sera. The Jokhang Temple, the Potala and Norbulingka palaces and Ganden, Drepung and Sera monasteries are key cultural relics under state-level protection. The southwest Tibet tourist district is a place for mountaineers. In southern Tibet, centered around Nyingchi, one can pass through the four seasons of the year in a single day. There are snow-capped mountains, dense primeval forests, surging rivers and azalea-covered mountainsides. New routes are Lhasa-Nyingschi-Shannan-Lhasa (eastern circle line) and Lhasa-Xigaze-Ngari-Xigaze (western circle line).