Is Longmen County classified as the source of the river?

Affixed to the source of the river. According to the Baidu map query, Longmen County is located in a county-level city in the central part of Guangdong Province and is affiliated with Heyuan City. It is located at the junction of the mountainous area in northern Guangdong and the two provinces of Guangdong and Guangxi, so it is classified as Heyuan. The geographical location of Longmen County is very important. It is located in the south-central part of Guangdong Province, bordering Hong Kong and Shenzhen to the south, Shaoguan and Heyuan to the north, Shanwei and Huizhou to the east, and Xiangqiao District of Guangdong Province to the west. It is a transportation hub in Guangdong Province.