Mesoamerican Barrier Reef System

The Mesoamerican Barrier Reef System (MBRS), also popularly known as the Great Mayan Reef or Great Maya Reef, is a marine region that stretches over 1,000 kilometres (620 mi) from Isla Contoy at the tip of the Yucatán Peninsula down to Belize, Guatemala and the Bay Islands of Honduras. The reef system includes various protected areas and parks including the Belize Barrier Reef, Arrecifes de Cozumel National Park, Hol Chan Marine Reserve (Belize), Sian Ka'an biosphere reserve, and the Cayos Cochinos Marine Park. Belize's coastline, comprising the Belize Barrier Reef, is home to approximately 80% of MBRS. The Belize Barrier Reef is the largest barrier reef in the northern hemisphere and the second largest barrier reef in the world. The Belize Barrier Reef and Belize's three offshore atolls, several hundred sand cays, mangrove forests, coastal lagoons and estuaries—collectively termed, the Belize Barrier Reef Reserve System—has been designated a World Heritage Site by UNESCO (1996).

The reef system extends along the coast of five countries: Mexico, Belize, Guatemala, and Honduras. It begins near Isla Contoy on the northern tip of the Yucatán Peninsula and continues south alongside the Riviera Maya including areas like Cozumel and Banco Chinchorro. It then continues south down the eastern coast of Belize including many cayes and atolls. It extends past the north-east corner of Honduras and ends in Nicaragua.

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