In the language of the Mayan peoples who once inhabited this region, Sian Ka'an means 'Origin of the Sky'. Located on the east coast of the Yucatán peninsula, this biosphere reserve contains tropical forests, mangroves and marshes, as well as a large marine section intersected by a barrier reef.

Tlacotalpan, a Spanish colonial river port on the Gulf coast of Mexico, was founded in the mid-16th century. It has preserved its original urban fabric to a remarkable degree, with wide streets, colonnaded houses in a profusion of styles and colours, and many mature trees in the public open spaces and private gardens.

Built in the 16th century by the Spanish on the ruins of Tenochtitlan, the old Aztec capital, Mexico City is now one of the world's largest and most densely populated cities. Xochimilco lies 28 km south of Mexico City. With its network of canals and artificial islands, it testifies to the efforts of the Aztec people to build a habitat in the midst of an unfavourable environment.

The ensemble of buildings, sports facilities and open spaces of the Central University City Campus of the Universidad Nacional Autónoma de México (UNAM) are an unique example of 20th-century modernism integrating urbanism, architecture, engineering, landscape design and fine arts with references to local traditions, especially to Mexico’s pre-Hispanic past.

The site is located in the central/southern portion of the Yucatán Peninsula, in southern Mexico and includes the remains of the important Maya city Calakmul, set deep in the tropical forest of the Tierras Bajas.The property also falls within the Mesoamerica biodiversity hotspot, the third largest in the world, encompassing all subtropical and tropical ecosystems.