Located in southwest China in northern Yunnan Province, the southern extent of the rugged Yun Mountains surround Lake Er (elongated dark feature center of image). Typically the local relief between the valley floors and mountain ridgelines is about 5000 feet (1525 meters). Most of the mountain ridgelines in this region of the Yun Mountains are in excess of 12000 feet (3660 meters) above sea level. Near the south end of Lake Er a highway (thin, light-colored line, top center) can be traced through the narrow, mountainous valleys that connect the city of Xiaguan (visible at southwest corner of the lake) with cities to the east (including Kunming the capital of Yunnan Province but not on this image). Rice is the predominant crop grown in the mountain valleys.