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 1,126 kilometres (700 mi) along the coasts of four countries – Mexico, Belize, Guatemala, and Honduras – from Isla Contoy at the northern tip of the Yucatán Peninsula south to Belize, Guatemala and the Bay Islands of Honduras. It is the second-longest reef system in the world.

It includes various protected areas and parks including the Punta Cancún, 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, including the Belize Barrier Reef, is home to approximately 30% of the Mesoamerican Barrier Reef System, with Mexico holding the largest share of the four countries, Honduras also with a substantial portion, and the smallest share of MBRS coastline being Guatemala.

It begins near Isla Contoy on the northern tip of the Yucatán Peninsula in Mexico and continues south alongside the entire Riviera Maya including areas like Cancún, Playa del Carmen, Tulum, Cozumel and on to the southernmost point of coastal Quintana Roo, with Banco Chinchorro and Xcalak. It then continues south along the eastern coast of Belize including many cayes and atolls. It extends to the north-east corner of Honduras. It is the largest barrier reef in the Western Hemisphere. In the world it is second largest after the Great Barrier Reef of Australia, yet the MBRS is much less researched and recognized.