Hailongdui (Hailongtun) is in Guizhou.

Hailongtun, also known as Hailongdui, is located in Hailongtun Village, Gaoping Town, Huichuan District, Zunyi City, Guizhou Province, at the top of Longyan Mountain about 28 kilometers northwest of Zunyi City's old city, also known as Hailonghuan, Longyanhuan, Longyantun, which is a "Tusi" castle ruins of the Song and Ming Dynasties. The highest altitude of 1354 meters above Tuen and 974 meters below Tuen, with a relative altitude difference of about 300~400 meters. The top of Tuen is flat and wide, with an area of about 1.59 square kilometers.

Hailongtun Tusi site was built in the Southern Song Dynasty Baoyou five years (1257), destroyed in the Ming Wanli twenty-eighth year (1600) of the battle of flat broadcasting, the site is an important remnant of the culture of Yang's Tusi of the Southwest Podcasting in the Song Dynasty, Yuan Dynasty and Ming Dynasty. There are nine passes built on Tun, six passes in front of Tun: Tongzhu Pass, Tizhu Pass, Feihu Pass, Feilong Pass, Chaotian Pass, Feifeng Pass; three passes after Tun: Wan'an Pass, Erdao Pass, Toudao Pass.

In 1982, Hailongtun was announced as a provincial-level cultural relics protection unit.In 2001, Hailongtun was announced by the State Council as one of the fifth batch of national key cultural relics protection units in China.On July 4, 2015, Hailongtun was inscribed on the World Heritage List in the 39th World Heritage General Assembly.

Featured Attractions of Hailongtun

1, Xiema Terrace

Xiema Terrace is a terrace connecting the upper and lower passes, whose architectural style is built according to the traditional craftsmanship of masonry, with standard pressed stone paving at the east, south and north edges, and stone mantle paving at the center of the terrace, which is also a military lookout post.

Ming Wanli years, broadcasting the twenty-ninth generation of Yang Yinglong expansion of Longyan Tuen and handwritten book mentioned the Longyan Tuen strict prohibited monument, the provisions of the management system of entry and exit of the Tuen need to be "finished post". Therefore, this place became a place where the people of Longyan Tun waited for the checking of the post, and the people who entered Longyan Tun had to check the post here before they could enter Feihu Pass.

2, the ladder

The ladder, the ancient name "36 steps", 55 meters long, slope 45 degrees, the middle step is 2.7 meters wide, the two sides of the parapet wall is 0.8 meters wide to connect the Feihu Pass. The whole ladder built on the steep mountain beams, is up and down the necessary passage.

3, the city wall

City wall is located in the edge of the surrounding Hailong Tun. Existing about 6,000 meters, winding closed, large-scale. Built in the Southern Song Dynasty, the Ming Dynasty reinforced and expanded. There are earth-built walls, walls made of rubble waste, and walls made of masonry with lime and glutinous rice paste, which are presumed to be relics of different eras.

Reference for the above: Baidu Encyclopedia-Hailongtun