Muyil was an ancient Mayan salt trading post a little south of present day Tulum. The ruin is the tallest on the Caribbean Coast. Our Mayan guide walked us through the jungle explaining plants and trees. I climbed the wooden tower for a view of the lagoon beyond. On that body of water were took boats, crossed through a mangrove island and entered a larger lagoon. There we inverted our life jackets and jumped into a canal of cool fresh water that carried us for 40 minutes toward the sea. These waterways were used by canoes to transport trade items. Near the end we surfaced onto a boardwalk that took us above mangrove on a more direct route back to our boats. This is part of the nature preserve Sian Ka’an, absolutely magnificent!