Peapack-Gladstone is a borough in Somerset County in the U.S. state of New Jersey. As of the 2010 Census, the borough's population was 2,582, reflecting an increase of 149 from the 2,433 counted in the 2000 Census, which had in turn increased by 322 from the 2,111 counted in the 1990 Census.
Peapack-Gladstone was incorporated as a borough by an act of the New Jersey Legislature on March 28, 1912, from portions of Bedminster Township, subject to the results of a referendum held on April 23, 1912. It is part of the New York metropolitan area, as well as the larger New York–Newark–Bridgeport, NY-NJ-CT-PA Combined Statistical Area and it is located within the Raritan Valley region.
Peapack is believed to have been derived from "Peapackton, ” a Lenape Native American term meaning "marriage of the waters", a reference to the confluence of the Peapack Brook and Raritan River in the area. Gladstone was named in honor of William Ewart Gladstone, who served as British Prime Minister several times between 1868 and 1894. In operation until the mid-1930s, the Moses Craig lime kiln is located at the center of Peapack.