Sri Lanka was known as Ceylon during the British rule and is now officially known as the Democratic Socialist Republic of Sri Lanka. Sri Lanka is also known as Serendib, Ceylon, the Bright Island, the Island of Dharma, and the Pearl of the Indian Ocean. Known by many different names in ancient times, the island was also known as the "Island of a Thousand Names". It is a South Asian island. It is located in the Indian Ocean, southwest of the Bay of Bengal and southeast of the Arabian Sea; it is separated from the Indian subcontinent by the Gulf of Mannar and the Palk Strait. Sri Lanka's location on major sea routes has made it a strategic maritime link between West Asia and Southeast Asia since ancient times. The Republic of India and the Republic of Sri Lanka signed an agreement on 23 March 1976 establishing maritime boundaries in the Gulf of Mannar and the Bay of Bengal. India and the Maldives are the closest countries to Sri Lanka.