The City of Leadville is a statutory city that is the county seat, the most populous community, and the only incorporated municipality in Lake County, Colorado, United States. The city population was 2,602 at the 2010 census and an estimated 2,762 in 2018. It is situated at an elevation of 10,152 feet (3,094 m). Leadville is the highest incorporated city in the United States and it is surrounded by two of the tallest 14,000 foot peaks in the state. Leadville is a former silver mining town that lies among the headwaters of the Arkansas River within the Rocky Mountains. The Leadville Historic District, designated a National Historic Landmark in 1961, contains many historic structures and sites of Leadville's mining era. In the late 19th century, Leadville was the second most populous city in Colorado, after Denver.