The Borough of Coraopolis is a small town on the western bank of the Ohio River, about ten miles from Pittsburgh, and surrounded for the most part by Moon Township, although the borough does share a boundary with Groveton to the east.
Early on in American history, the Coraopolis area was literally the "fronteir" and a military facility, Fort Vance, was established to protect settlers. The current Vance Avenue is named after the fort's builder, Captain Robert Vance. The Vancefort name was used for the post office after the town became known as Middletown, but in 1886 the name Coraopolis was introduced.
Coraopolis is traversed by the rails of CSX's Pittsburgh Subdivision; until 1993 this was the Pittsburgh & Lake Erie Railroad. The P&LE, known as the "Little Giant", was a pivotal part of the region's steelmaking industries, bringing in raw materials the the steel mills in Pittsburgh and Aliquippa. At one point, there were as many as four tracks running through Coraopolis, but at present the double trackage switches to a single line underneath the Neville Island Bridge.
The former P&LE passenger station at Mill Street still stands, although it has been empty for some time. The passenger platform on the other side of the tracks is, however, long gone. There is a former freighthouse nearby, which is still in (non railroad) use. P&LE passenger trains from College to Pittsburgh, a remnant of a much larger passenger operation, continued as late as the mid-1980s before being discontinued. As of February 2011, the pedestrian bridge over the tracks at Chestnut Street still stands, although this was closed some time ago, and is due to be demolished as part of the plan to rehab the Pittsburgh Subdivsion for double-height trains.
Coraopolis was also once the site of the headquarters of the Montour Railroad, a coal hauler that interchanged with the P&LE at Montour Junction, under the bridge. The Montour, which in later years was controlled by the P&LE, faded away as the region's mines closed, and the right of way is now the Montour Trail. The former Montour yard has been vacant and overgown for years, with the railroad facilities removed, and Allegheny County is to redevelop the area for sporting facilities.
Coraopolis once had a number of neighborhood schools, including one on State Avenue, another at School Street and Ridge Avenue, another on Ridge several blocks east, and Lincoln School on the west side of town. As populations fell, maintaining these separate schools became a burden, and the Cornell Education Center was built in the mid-1970s to replace them. The School and State Ave. buildings still exist and are used as apartments, but the Ridge Avenue and Lincoln schools have been torn down.
Coraopolis is often cited as hosting the former Nike-Hercules missile site PI-71, but the launch site for PI-71 was actually in Moon Township, while the controlling radar station was in Robinson Township. There can be some confusion with Coraopolis addresses, as Coraopolis shares the 15108 zip code with Moon Township, and the main Coraopolis post office is in Moon.