Belle Vernon is a borough in Fayette County, Pennsylvania, United States. It is situated along the Monongahela River, abutting two other counties, Westmoreland to the north and Washington across the river. As of the 2020 census, Belle Vernon had a population of 1,025.

Fayette County is a county in the Commonwealth of Pennsylvania. It is located in southwestern Pennsylvania, adjacent to Maryland and West Virginia. As of the 2020 census, the population was 128,804. Its county seat is Uniontown. The county was created on September 26, 1783, from part of Westmoreland County and named after the Marquis de Lafayette. The county is part of the Southwest Pennsylvania region of the state.