Princeton Junction is an unincorporated community and census-designated place (CDP) located within West Windsor, in Mercer County, in the U.S. state of New Jersey. As of the 2010 United States Census, the CDP's population was 2,465.
Following the mid-1860s relocation of the Camden & Amboy rail line from next to the Delaware & Raritan Canal to the present location of the Northeast Corridor, and the subsequent construction of a train station south of the intersection of Washington Road and the new rail line, a community called "Princeton Junction" developed. This community originally featured several farmhouses, a hotel, a general store, a feed mill, and several other businesses centered around the intersection of Station Drive & Washington Road, profiting off of access to other cities provided by the rail line.
The construction of the neighborhood of Berrien City (focused around Scott Avenue, Alexander Road, and Berrien Avenue) represented West Windsor's first plan