The Yucatán Peninsula is a large peninsula in southeast Mexico and adjacent portions of Belize and Guatemala. The peninsula extends towards the northeast, separating the Gulf of Mexico to the north and west of the peninsula from the Caribbean Sea to the east. The Yucatán Channel, between the northeastern corner of the peninsula and Cuba, connects the two bodies of water. The peninsula is approximately 181,000 km2 (70,000 sq mi) in area. It has low relief and is almost entirely composed of porous limestone. The peninsula lies east of the Isthmus of Tehuantepec, the narrowest point in Mexico separating the Atlantic Ocean, including the Gulf of Mexico and Caribbean Sea, from the Pacific Ocean. Some consider the isthmus to be the geographic boundary between Central America and the rest of North America, placing the peninsula in Central America. Politically, all of Mexico, including the Yucatán, is generally considered part of North America, while Guatemala and Belize are considered part of Central America. Video credit © Grindstone Media Group/Walter Arce/ZUMA Press