Gansu has a developed tourist industry. The world-famous ancient Silk Road once passed through the province and left a great number of historic relics. The national major scenic areas include Mt.Maiji, Mt.Kongdong, Mingsha Hill-Yueya (crescent) Spring, and Jiayuguan Pass, etc. Mogao Grottoes in Dunhuang were listed in the World Heritages in 1987 by UNESCO. Other Historic sites, such as Binglingsi Grottoes, Yulin Grottoes, Shuiliandong Grottoes, Labrang Temple. Haizang Temple etc, are all well-known to tourists.