The waters around Playa del Carmen are ideal diving territory :the colourful corals form part of the gigantic Mesoamerican Reef, the world's second biggest barrier reef system. And one of the best parts is that the dive sites are close to shore :between 10 and 20 minutes' boat ride away. You'll be doing a drift dive :where you're gently moved along by the current :and you'll have an experienced guide with you the whole way. The boat will follow the bubbles, so it'll be ready to pick you up when you get to the end. Dive depths vary between 30 and 100 feet, but whichever site we head to, you can expect to clap eyes on the likes of reef sharks, sea turtles and barracuda.