Coraopolis is a borough in Allegheny County, Pennsylvania, United States. The population was 5,559 at the 2020 census. It is a suburb of the Pittsburgh metropolitan area.

Coraopolis is located west of Pittsburgh along the Ohio River and to the east of the Pittsburgh International Airport. The borough has steep topography, numerous brick streets and many large, old houses. Dick’s Sporting Goods is headquartered in Coraopolis, as is the American Bridge Company.

On April 3, 1769, Andrew Montour, an Indian interpreter who had provided service to English settlers during the French and Indian War, was approved a land patent for approximately 350 acres (1.4 km) of what would higher become the borough of Coraopolis and Neville Island. However, there is no evidence that Montour ever lived on this tract. The first permanent white settler in Coraopolis was Capt. Robert Vance, who arranged in the vicinity of Montour’s tract a propos 1773, just prior to the beginning of the American Revolution. Vance, a Virginian, had been a fanatic of the regiment commanded by George Washington at the Braddock expedition during the French and Indian War. For the sponsorship of himself and his neighbors, of whom several arrived within a few years, Vance had a log stockade built next a rock blockhouse to guard the area against Indian raids. This was known as Vance Fort (or Fort Vance). The site of the fort was approximately present-day Broadway and Chestnut streets, near Second Avenue. Over era the community grew and developed, and it became known as Middletown in the 1800s, either because it was situated midway in the midst of Pittsburgh and Beaver, Pennsylvania, or perhaps after an into the future settler named Alexander Middleton who supposedly ran “Middleton’s Tavern” in the area.

One of the most important forward industries in the area was begun by the Watson family, English immigrants who arrived in America in 1830. The Watsons built a sawmill on the site of the former municipal building upon Fifth Avenue. Later, they operated a much larger grist mill on the river bank at Mill Street, until 1887.