The Sian Ka'an ("where the sky is born," pronounced see-an caan) region was first settled by the Mayans in the 5th century AD. In 1986 the Mexican government established the 1.3-million-acre Reserva de la Biosfera Sian Ka'an as an internationally protected area. The next year, it was named a World Heritage Site by UNESCO (United Nations Educational, Scientific, and Cultural Organization); later, it was extended by 200,000 acres. The Riviera Maya and Costa Maya split the biosphere reserve; Punta Allen and north belong to the Riviera Maya, and everything south of Punta Allen is part of the Costa Maya.
The Sian Ka'an reserve constitutes 10% of the land in Quintana Roo and covers 100 km (62 mi) of coast. Hundreds of species of local and migratory birds, fish, other animals and plants, and fewer than 1,000 residents (primarily Mayan) share this area of freshwater and coastal lagoons, mangrove swamps, cays, savannas, tropical forests, and a barrier reef. There are approximately 27 ruins (none excavated) linked by a unique canal system—one of the few of its kind in the Mayan world in Mexico. This is one of the last undeveloped stretches of North American coast. There's a $4 entrance charge. To see Sian Ka'an's sites you must take a guided tour.
Several kinds of tours, including bird-watching by boat, and night kayaking to observe crocodiles, are offered on-site through the Sian Ka'an Visitor Center (998/884-3667, 998/884-9580, or 998/871-0709. www.cesiak.org), which also offers five rooms with shared bath and one private suite for overnight stays. Prices range from $65 to $90 and meals are separate. The visitor center's observation tower offers the best view of the Sian Ka'an Biosphere from high atop their deck and wood bridge.
Other privately run tours of the reserve and surrounding area are also available. Tres Palmas (998/871-0709; 998/845-4083 cell. www.trespalmasweb.com) runs a day tour that includes a visit to a typical Mayan family living in the biosphere, a tamale breakfast, a visit to the Mayan ruins at Muyil, a jungle trek to a lookout point for bird-watching, a boat trip through the lagoon and mangrove-laden channels (where you can jump into one of the channels and float downstream), lunch on the beach beside the Mayan ruins at Tulum, and a visit to nearby cenotes for a swim and snorkeling. The staff picks you up at your hotel; the fee of $129 per person includes a bilingual guide.
Many species of the once-flourishing wildlife have fallen into the endangered category, but the waters here still teem with rooster fish, bonefish, mojarra, snapper, shad, permit, sea bass, and crocodiles. Fishing the flats for wily bonefish is popular, and the peninsula's few lodges also run deep-sea fishing trips.
To explore on your own, follow the road past Boca Paila to the secluded 35-km (22-mi) coastal strip of land that's part of the reserve. You'll be limited to swimming, snorkeling, and camping on the beaches, as there are no trails into the surrounding jungle. The narrow, extremely rough dirt road down the peninsula is filled with monstrous potholes and after a rainfall is completely impassable. Don't attempt it unless you have four-wheel drive. Most fishing lodges along the way close for the rainy season in August and September, and accommodations are hard to come by. The road ends at Punta Allen, a fishing village whose main catch is spiny lobster, which was becoming scarce until ecologists taught the local fishing cooperative how to build and lay special traps to conserve the species. There are several small, expensive guesthouses. If you haven't booked ahead, start out early in the morning so you can get back to civilization before dark.
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