Tulum, a town on the Caribbean coastline of Mexico’s Yucatán Peninsula is a UNESCO World Heritage Site. One of the most important sites in Tulum is its Mayan ruins, located on a cliff facing the Caribbean Sea, the only archaeological site that sits on the seashore. The main building is a large stone structure called El Castillo (castle), perched on a rocky cliff above the white sand beach and turquoise sea. Under the cliff is Paradise Beach, considered one of the best beaches in the Riviera Maya, from which excursions are organised to the famous Mesoamerican Reef Barrier. The Sian Ka’an Biosphere Reserve measures half a million hectares and covers all possible scenarios: beaches, coral reefs, rainforest, dunes and natural wells. Near the ruins is the Parque Nacional Tulum, a coastal area with mangroves and cenotes (natural limestone sinkholes).The Gran Cenote of Tulum is the most famous cenote in the region. It’s a favourite of swimming, snorkeling and cave-diving enthusiasts.