Georges Island is one of the islands in the Boston Harbor, situated just over 7 miles (11 km) from downtown Boston. The island has a permanent size of 39 acres (160,000 m2), plus an intertidal zone of a further 14 acres (57,000 m2), and rises to a height of 50 feet (15 m) above sea level. Historic Fort Warren is on the island. Because of this, and since a ferry operates from Boston to the island, it is a popular destination and one of the easiest islands to access in the Boston Harbor Islands National Recreation Area.