High Quality Content by WIKIPEDIA articles! Princeton is a community located in Mercer County, New Jersey, United States. It is best known as the location of Princeton University, which has been sited in the community since 1756. Although Princeton is a "college town", there are other important institutions in the area, including the Institute for Advanced Study, Educational Testing Service (ETS), Opinion Research Corporation, Siemens Corporate Research, Bristol-Myers Squibb, Sarnoff Corporation, FMC Corporation, The Robert Wood Johnson Foundation, Amrep, Church and Dwight, Berlitz International, and Dow Jones Company.