Yanhe County belongs to tongren city. Yanhe County is 98.28km long from north to south and 53km wide from east to west, with a county area of 2483.5 1 km2, accounting for 1.4% of the total area of the province and 13.7% of the total area of the whole region. Tujia Autonomous County along the river is located in the northeast corner of Guizhou Province, north of tongren city, downstream of Wujiang River, bordering Pengshui and Youyang County in Chongqing in the north and east respectively.

Along the river, it belongs to subtropical monsoon humid climate zone. Annual average temperature 13 ~ 18℃, annual precipitation 1050 ~ 1220 mm, annual sunshine 1 100 ~ 1400 hours. The climate is warm and humid, and the water, heat, light and temperature are synchronized, which is suitable for the growth, development and reproduction of many animals, plants, microorganisms and other organisms.

Terrain along the river.

Tujia Autonomous County along the river is located in the crisscross zone of the northeast slope of Guizhou Plateau, Dalou Mountain Range and Wuling Mountain Range. Wujiang River divides Yanhe County from south to north into two parts: northwest and southeast, with Dalou Mountain in the northwest and Wuling Mountain in the southeast. There are 88 15 peaks, with an average of 3.6 mountains per square kilometer. The highest altitude is 1462m, and the lowest altitude is 225m. Mountains account for 69.9%, hills for 27% and dams for 3. 1%. Karst area accounts for 72.5% and non-karst area accounts for 27.5%, which is a typical karst mountain area.