Sediments frame the Yucatán Peninsula, which comprises the Mexican states of Yucatán, Campeche, and Quintana Roo; the northern part of the nation of Belize; and Guatemala’s northern El Petén Department. Several lagoons and bays are also visible near the shoreline, including Terminos Lagoon, on the west coast in the lower left quadrant, and Chetumal Bay, on the east coast at the center right.
Chetumal Bay is a large bay in northern Belize and eastern Mexico in the south of the Yucatán Peninsula. On the bay is the major city of Chetumal, in the Mexican state of Quintana Roo. The mouth of the bay is redirected southward and buffered by a large Belizean island named Ambergris Caye. The bay is a part of the Caribbean Sea.
North of the bay is another smaller bay that is part of the Sian Ka’an Biosphere Reserve, in the municipality of Tulum in the Mexican state of Quintana Roo.. It has been a Mexican national park since 1986. and a UNESCO World Heritage Site since 1987. Part of the reserve is on land and part is in the Caribbean Sea, including a section of coral reef. The reserve has an area of 5,280 km².
Click here for FULL sized image, the large version you see when you click the above photo is reduced by 50% in size