Gangu County, subordinate to Tianshui City, Gansu Province, is located in the southeast of Gansu Province, the northwest of Tianshui City, and the upper reaches of the Weihe River. Gangu County has a temperate continental monsoon climate with a total area of 1572.6 square kilometers. By the end of 2021, the permanent population of Gangu County was 501800.

Gangu, known as "Ji" in ancient times, is an important birthplace of the Qin people and the birthplace of the Chinese county government. It was established in 688 BC, with a history of more than 2700 years, and is known as "the first county in China". In 1958, Gangu and Zhangxian were abolished and merged into Wushan County. In 1962, the original Gangu County was restored. As of October 2021, Gangu County has 13 towns and 2 townships under its jurisdiction.

There are many cultural relics and historic sites in Gangu County, and it has successively won the titles of "National Pepper Town", "China Apple Town", "China Pepper Town", and "National Wushu Town".

In 2020, Gangu County will achieve a GDP of 7.931 billion yuan, with an average annual growth of 5.94%.