Washington Rock State Park is a 52-acre (0.21 km2) scenic state park on top of the first Watchung Mountain in Green Brook, New Jersey. The park is operated and maintained by the New Jersey Division of Parks and Forestry.It is famous for its scenic overlook used by General George Washington in 1777 to monitor Continental Army troops led by British General William Howe at the Middlebrook encampment. The 30-mile (48 km) panoramic vista covers the eastern plains of New Jersey up to New York City.The land was bought in 1913 to establish the park and commemorate the events of 1777. Most of it is woodland but at the outlook there are walking trails and a picnic area.