Getting wet at Xel-Ha, another eco-adventure park, feels good after a walk through Tulum, eight miles away. We swim in Xel-Ha’s lagoon; float on inner tubes, down a river that winds through a mangrove forest; and then relax in a hammock on the beach. Kids can practice snorkeling in the calm lagoon, although there’s not much to see. At Children’s World, kids splash in a wading pool, cross a rope bridge and play on the swings. Avoid the park when big ships are in port.