The Belize Barrier Reef is a series of coral reefs straddling the coast of Belize, roughly 300 meters (1,000 ft) offshore in the north and 40 kilometers (25 miles) in the south within the country limits. The Belize Barrier Reef is a 300 kilometers (186 miles) long section of the 900 kilometers (560 mi) long Mesoamerican Barrier Reef System, which is continuous from Cancún on the northeast tip of the Yucatán Peninsula through the Riviera Maya up to Honduras making it the second largest coral reef system in the world after the Great Barrier Reef in Australia. It is Belize’s top tourist destination popular for scuba diving and snorkeling and attracting almost half of its 260,000 visitors, and vital to its fishing industry. Because of its exceptional natural beauty, significant on-going ecological and biological processes, and the fact that it contains the most important and significant natural habitats for in-situ conservation of biological diversity (criteria VII, IX, and X), the Reserve System has been designated as a World Heritage Site since 1996.
A large portion of the reef is protected by the Belize Barrier Reef Reserve System, which includes seven marine reserves, 450 cays, and three atolls. It totals 960 km² (370 miles²) in area, including: Glover’s Reef Marine Reserve, Great Blue Hole, Half Moon Caye, Hol Chan Marine Reserve.
Cays include: Ambergris Caye, Caye Caulker, Caye Chapel, St. George’s Caye, English Caye, Rendezvous Caye, Gladden Caye, Ranguana Caye, Long Caye, Maho Caye, Blackbird Caye, Three Corner Caye, Northern Caye, Sandbore Caye.