Raritan Bay is a bay located at the confluence of the Raritan River and the Arthur Kill between the U.S. states of New York and New Jersey. The bay, which is just south of the important New York Harbor, is bounded on the north by New York's Staten Island and Lower New York Bay, on the west by Perth Amboy, New Jersey, on the south by the Raritan Bayshore communities of Monmouth County, New Jersey, and on the east by Sandy Hook Bay. The bay is named after the Native American Raritans, a branch of the Lenape tribe who lived in the vicinity of the bay at the time of the arrival of Dutch colonists in the 17th century.