Mercer County is a county on the southeastern border of the U.S. state of West Virginia. At the 2010 census, the population was 62,264. Its county seat is Princeton. The county was originally established in the State of Virginia by act of its General Assembly on March 17, 1837, using lands taken from Giles and Tazewell counties. Mercer County is part of the Bluefield, WV-VA Micropolitan Statistical Area.

Mercer County is a county on the southeastern border of the U.S. state of West Virginia. At the 2010 census, the population was 62,264. Its county seat is Princeton. The county was originally established in the State of Virginia by act of its General Assembly on March 17, 1837, using lands taken from Giles and Tazewell counties. Mercer County is part of the Bluefield, WV-VA Micropolitan Statistical Area.

Tazewell County () is a county located in the southwestern portion of the U.S. state of Virginia. As of the 2010 census, the population was 45,078. Its county seat is Tazewell.Tazewell County is part of the Bluefield, WV-VA Micropolitan Statistical Area. Its economy was dependent on coal and iron of the Pocahontas Fields from the late 19th into the 20th century.

Wytheville () is a town in, and the county seat of, Wythe County, in southwestern Virginia, United States. It is named after George Wythe, a signer of the United States Declaration of Independence, and mentor to Thomas Jefferson. Wytheville's population was 8,211 at the 2010 census. Interstate Highways 77 and 81 were constructed to intersect at the town, long a crossroads for travelers. During the American Civil War, Wytheville had a strategic importance. It was attacked in 1863 (Toland's Raid) and 1865 (Stoneman's 1865 Raid). The town is the birthplace of Edith Bolling Wilson, second wife of President Woodrow Wilson.