Sian Ka'an, is a Mayan phrase for "Where The Sky Is Born," was the first established Biosphere Reserve in Mexico. It is currently a UNESCO World Heritage site and remains a high priority of protection for the state of Mexico.

As the third largest protected area in Mexico, the Sian Ka'an Biosphere Reserve comprises 1.3 million acres of tropical ecosystems in the State of Quintana Roo. Consisting of lowland forest, flooded savannas, mangroves, and a portion of the world's second largest coastal barrier reef – the Mesoamerican Barrier Reef – the Reserve is home to 800 plant species and provides habitat for 350 species of birds, as well as jaguar, puma, ocelot, spider and howler monkeys, crocodiles, and many types of turtles. Additionally, the Sian Ka'an Biosphere Reserve is home to 23 different archaeological sites of pre-Columbian culture.