Moon Hill is a hill with a natural arch through it a few kilometers outside Yangshuo in southern China's Guangxi autonomous region. It is so named for a wide, semicircular hole through the hill, all that remains of what was once a limestone cave formed in the phreatic zone. Like most formations in the region, it is karst. It has an elevation of 380 m (1,250 ft), while the hill is 230 m (750 ft) in relative height and 410 m (1,350 ft) in length. The arch is about 50 meters in height.