This Valley, with the richest biodiversity in North America, consisting of Zapotitlán-Cuicatlán, San Juan Raya and Purrón, it is one of the main centres of diversification for the cacti family, which is critically endangered worldwide. The valley presents an exceptional water management system of canals, wells, aqueducts and dams, the oldest in the continent.

This archipelago is part of a submerged mountain range, with the four islands representing the peaks of volcanoes emerging above sea level. The islands provide critical habitat for a range of wildlife and are of particular importance for seabirds.

The 714,566 hectare site comprises two distinct parts: the dormant volcanic Pinacate Shield of black and red lava flows and desert pavements to the east, and, in the west, the Gran Altar Desert with its ever changing and varied sand dunes that can reach a height of 200 metres.

Located in the central part of the peninsula of Baja California, the sanctuary contains some exceptionally interesting ecosystems. The coastal lagoons of Ojo de Liebre and San Ignacio are important reproduction and wintering sites for the grey whale, harbour seal, California sea lion, northern elephant-seal and blue whale. The lagoons are also home to four species of the endangered marine turtle.

The site comprises 244 islands, islets and coastal areas that are located in the Gulf of California in north-eastern Mexico. The site is home to 695 plant species and 891 of fish; has a striking natural beauty in a dramatic setting formed by rugged islands with high cliffs and sandy beaches, which contrast with the brilliant reflection from the desert and the surrounding turquoise waters.

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.

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.