Ruins of an ancient Mayan harbor.
Tulum is a city on the Caribbean coast of Mexico, in the Yucatan Peninsula. It is known for its well-preserved ruins of an ancient Mayan harbor. The main building is a large stone structure called El Castillo, which stands on the top of a rocky cliff, on the white sand beaches and the turquoise sea. Near the ruins, there is the Tulum National Park, a coastal area with mangroves and cenotes.