The U.S. Virgin Islands is an unincorporated organized territory of the United States of America between the Caribbean Sea and the North Atlantic Ocean, east of Puerto Rico. It was formerly known as the Danish West Indies. Together with the British Virgin Islands, to the northeast, the territory forms the Virgin Islands archipelago. These islands are in an important location along the Anegada Passage - a key shipping lane for the Panama Canal; Saint Thomas has one of the best natural deep water harbours in the Caribbean.
The terrain is mostly hilly to rugged and mountainous with little level land. There are occasional earthquakes. The highest point is Crown Mountain at 474m. During the 17th century, the archipelago was divided into two territorial units, one English and the other Danish.