Virgin Islands National Park occupies the majority of St. John, one of the U.S. Virgin Islands. Many of the beaches are fringed by coral reefs. They include Trunk Bay, backed by forests, and Francis Bay, whose calm waters are home to sea turtles. Annaberg Plantation has the ruins of an 18th-century sugar plantation. Trails through tropical forests lead to the ruins of Reef Bay Sugar Mill, in the south.