Aspinwall is a borough on the Allegheny River in Allegheny County, Pennsylvania, United States, and is part of the Pittsburgh Metro Area. In 1900, 1,231 people lived in Aspinwall, and that number rose to 2,592 in 1910, and 3,170 by 1920. The population was 2,801 at the 2010 census.
Aspinwall is located at 40°29′35″N 79°54′11″W.
According to the United States Census Bureau, the borough has a total area of 0.4 square miles (1.0 km2), of which 0.3 square miles (0.78 km2) is land and 0.04 square miles (0.10 km2) is water. Its average elevation is 758 feet (231 m) above sea level.
Aspinwall is bordered by Sharpsburg to the west and O'Hara Township to the northwest, north and east. Adjacent to Aspinwall across the Allegheny River to the south are the Pittsburgh neighborhoods of Highland Park and the southern section of Lincoln-Lemington-Belmar.
In the mid-1880s, the area which is now Aspinwall was primarily owned by the descendants of James Ross, but as the steel industry was thriving in Pittsburgh, Henry Warner, superintendent of the Allegheny County Workhouse, had the idea of creating a residential community along the bank of a river.
Warner traveled to New York to discuss the idea with Annie Aspinwall. He purchased 155 acres (0.63 km2) of land from her and formed the Aspinwall Land Company in 1890. Pittsburghers, mostly from the upper-middle class, purchased lots from the 60 available home sites. By 1890, the town had 400 residents, most of whom were young couples with children.