Another local jewel you’ll want to explore is the Mayan Ruins of Tulum – the only Mayan city built next to the ocean. Its magic lies in the fact that there are so many underground rivers, the Mayans believed this region was floating and unattached to the earth. Built in the 10th century, this walled Maya city-state functioned as a seaport. The dominating structure in the ruins is the Castillo (castle), which served as a fortress as well as a temple. You can stroll in and around the structures, and enjoy a variety of shows and presentations.