Hongdong (tong) County, belongs to Linfen City, Shanxi Province, is located in the south of Shanxi Province, the north end of Linfen Basin, east Huoshan and GuXian County, west Luliang and Pu County, north Huozhou, Fenxi adjacent, south bordering Yaodu District, a total area of 1494 square kilometers. It has jurisdiction over 10 towns and 5 townships.

Hongdong was named after Hongya in the south of the city and Ancient Cave in the north of the city. In the Western Zhou Dynasty, Hongdong was called the State of Yang Hou. After the unification of the six States in Qin Dynasty, the system of prefectures and counties was implemented, and Hongdong was called Yang County. In the second year of Sui Yining (618), Yang County was changed into Hongdong, which has been passed down ever since. Hongdong County is one of the origins of the ancient civilization of the Chinese nation, known as the "hometown of the Chinese people". There are more than 250 cultural attractions and natural landscapes in Hongdong. From ancient myths and legends to clear written records, only half of the 26 ancient figures listed in the Dictionary of Famous People in the Past Dynasties of China can be found in Hongdong. Hongdong Big Locust Tree is the only sacred place for people's sacrifice in China with the themes of "Searching for roots" and "ancestor worship". It is a key cultural relic protection unit in Shanxi Province and the largest folk ancestor worship shrine in China, honored as "the Sacred Place for roots and ancestors", "the hometown of the world and the hometown of the Chinese".

By the end of 2021, Hongdong County has a permanent population of 627,700. In 2021, the GDP of Hongdong County reached 19.515 billion yuan, of which the added value of the primary industry was 1.436 billion yuan, that of the secondary industry was 10.065 billion yuan and that of the tertiary industry was 8.014 billion yuan. The ratio of three industries is 7.4:51.6:41.0.