Mount Heng, also known as Nanyue, Shouyue, or Nanshan, is mainly located in Nanyue District of Hengyang City, Hengshan County, and the eastern part of Hengyang County in Hunan Province. According to the Ganshi Xingjing from the Warring States period, it is named Mount Heng because it lies on the wing of the Zhen star among the twenty-eight lunar mansions — "its changes correspond to the armillary sphere" and "it weighs virtue and balances things" — like a steelyard that can weigh heaven and earth.
The main peaks of Mount Heng include Huiyan Peak, Zhurong Peak, Zigai Peak, and Yuelu Mountain, among which the highest peak, Zhurong Peak, stands at 1,300.2 meters above sea level. The main body of Mount Heng lies between 27°4′–27°20′ N and 112°34′–112°44′ E, running northeast–southwest. It extends from Futianpu Township in Hengshan County in the north to Zhangmu Township in Hengyang County in the south, and from Jiepai Town in Hengyang County in the west to Nanyue District of Hengyang City in the east, stretching 38 kilometers long and 17 kilometers at its widest, with a total area of 640 square kilometers.
Mount Heng is a famous sacred site of both Daoism and Buddhism in China, with more than 200 temples, shrines, convents, and monasteries around the mountain. It is the place where the ancient rulers Tang Yao and Yu Shun patrolled their territories, hunted, and offered sacrifices to the gods of land and grain, and where Yu the Great killed a horse to sacrifice to heaven and earth in search of a method to control the floods. The mountain god of Mount Heng is the fire god Zhurong, worshipped in folk belief. He was appointed by the Yellow Emperor to guard Mount Heng, taught the people to use fire, and nurtured all things. After his death, he was buried at Chidi Peak of Mount Heng and is honored by the locals as the Holy Emperor of Nanyue. Of Daoism's "Thirty-Six Grotto-Heavens and Seventy-Two Blessed Lands," four are located in Mount Heng. Two genuine sarira relics of Shakyamuni Buddha are enshrined in the Vajra Sarira Pagoda of Nantai Temple on Mount Heng.
In May 2007, the Nanyue Mount Heng tourist area in Hengyang City, where Mount Heng is located, was rated among the first batch of national 5A-level tourist attractions.