The Virgin Islands National Park is an American national park preserving about 60% of the land area of Saint John in the United States Virgin Islands, as well as more than 5,500 acres (2,226 ha; 9 sq mi) of adjacent ocean, and nearly all of Hassel Island, just off the Charlotte Amalie, Saint Thomas harbor. The park is well-known for scuba diving and snorkeling, and has miles of hiking trails through the tropical rainforest.