Formed February 26, 1773 (11th county)
Westmoreland County (354,663), Greensburg (14,969), Murrysville (20,986)
The Beaux Arts masonry building was built in 1906. It sits on Main Street at Pittsburgh Street. United States Highway 119 is one block north of the courthouse. There was also an 1854 version. William Kaufman is the building designer. The facility was enlarged in 1978. The county was organized on February 26, 1773 as the 11th county. Hannastown was the first county seat until 1782 when Greensburg took the role. Westmoreland County is named for Westmoreland County, England. The county seat is named for Revolutionary War General Nathanael Greene. He is also the namesake of Greene County. Westmoreland County is the birthplace of 2 Pennsylvania governors, William F. Johnston and John W. Geary.
Westmoreland County government consists of a sheriff and 3 Commissioners. Fourteen Common Pleas Court Judges and Seventeen Magistrate Court Judges serve Westmoreland County. The county is in the western part of Pennsylvania. Pittsburgh, Pennsylvania is directly west and Erie, Pennsylvania is northwest of the county. The Allegheny River forms its northwest border and the Monongahela River forms its southwest border. The county center is 8 miles Southeast of Greensburg nearer Pleasant Unity. The county is surrounded clockwise by Armstrong, Indiana, Cambria, Somerset, Fayette, Washington, Allegheny, and Butler counties.
The area of the county is 1036 square miles. It is 9 out of 67 in the state. It ranks 11 out of 67 in population in the state. It has a density of 342.3 persons per square mile making it 18 out of 67 in the state. Westmoreland County has 40.8% of its population in its incorporated areas. Interstate Highway 70 passes through the county from east to west from Somerset County to Washington County. Interstate Highway 76 enters joined with Interstate Highway 70 from Somerset County, splits and continues west into Allegheny County. United States Highway 22 goes east to west from Indiana County to Allegheny County. United States Highway 30 parallels Interstate Highway 76 from Somerset to Allegheny counties. United States Highway 119 is joined with United States Highway 22 from Indiana County, splits and continues south into Fayette County. The county resembles a T-shirt leaning northwest. Greensburg is in the western third of the county. Murrysville is located on the western border of the county. Greensburg is the county seat and Murrysville is the largest city. Greensburg is 4.2% of the county population while Murrysville is 5.9% of the county population. This county is in the Pittsburgh Metropolitan Statistical Area.
Adamsburg
Arnold
Arona
Avonmore
Bolivar
Delmont
Derry
Donegal
East Vandergrift
Export
Greensburg
Hunker
Hyde Park
Irwin
Jeannette
Latrobe
Laurel Mountain
Ligonier
Lower Burrell
Madison
Manor
Monessen
Mount Pleasant
Murrysville
New Alexandria
New Florence
New Kensington
New Stanton
North Belle Vernon
North Irwin
Oklahoma
Penn
Scottdale
Seward
Smithton
South Greensburg
Southwest Greensburg
Sutersville
Vandergrift
West Leechburg
West Newton
Youngstown
Youngwood
Trafford