The Town of Winthrop is a municipality in Suffolk County, Massachusetts, United States. It is an oceanside suburban community in Greater Boston situated at the north entrance to Boston Harbor and is very close to Logan International Airport. The town is a peninsula, 1.6 square miles (4.2 km2) in area, connected to Revere by a narrow isthmus and to East Boston by a bridge over the harbor inlet to the Belle Isle Marsh Reservation. Settled in 1630, Winthrop is one of the oldest communities in the United States. It is also one of the smallest and most densely populated municipalities in Massachusetts.