Sian Ka'an Biosphere Reserve covers approximately 1.3 million acres of central Quintana Roo. It was established as part of UNESCO's Man and the Biosphere Program in 1986, and in 1987 it was declared a UNESCO World Heritage Site.

In Maya, Sian Ka'an means "where the sky is born" or "gift from the sky." It was inhabited in the Maya Classic and Post Classic Periods, and has 23 known archeological sites. The northern part was a trade route between two important city states, Tulum and Muyil. With an infrastructure of man-made channels connecting existing lagoons.

Currently about 2,000 people live in the area, especially in the coastal regions, where Punta Allen and Punta Herrero are the largest fishing communities. It is the home to more than  100 species of mammals, 336 species of birds, and the the nesting ground for many wading birds, and two species of endangered turtles.

Human activity in the Reserve is highly restricted. In more than half of its total area only scientific research is permitted. There are some parts where sustainable development projects are allowed; and only around 1% of the total area is privately owned.

Sian Ka'an's conservation challenge is to promote low-impact human activities in order to protect all forms of life within its boundaries. For this purpose, the Mexican Government works together with private NGOs, like Amigos de Sian Ka'an.