The national park is home to tropical rainforest, tall mountains, beaches, and some of the tallest sea cliffs in the world (). It was authorized by the U.S. Congress in 1988 to preserve the paleotropical rain forest, Indo-Pacific coral reefs, and Samoan culture. It officially opened in 1993 when a 50-year lease was signed between the U.S. federal government, the government of American Samoa, and local village chiefs (Matai). It is the only U.S. National Park where the U.S. federal government leases the land from local governments instead of being the land owner. It is a  park which provides habitat for a variety of tropical wildlife, including coral reef fish, seabirds, flying fruit bats, and numerous other species of animals. Approximately  are on Tutuila, and the remainder is on the other islands and the ocean. The park's offshore coral reefs provide habitat for 1,000 species of coral reef and pelagic fishes. The park is home to over 150 species of coral. Notable terrestrial species are the Pacific tree boa and the Flying Megabat, which has a  wingspread.