The Virgin Islands are the western island group of the Leeward Islands, which are the northern part of the Lesser Antilles, and form the border between the Caribbean Sea and the Atlantic Ocean. Politically, the eastern islands form the British Virgin Islands and the western ones form the United States Virgin Islands. The British Virgin Islands is an overseas territory of the United Kingdom comprising approximately 60 islands and cays including Tortola, Virgin Gorda, Jost Van Dyke, and Anegada.