Kayak, swim with the manatees, dive or snorkel. You can do it all in the crystalline waters of Belize. Ambergris Caye, its biggest island, draws the majority of tourists who come to this western Caribbean nation. A scuba nirvana, Ambergris Caye sits just one-half mile from the Belize Coral Reef System, the second-biggest coral reef in the world. When not exploring the reef, visitors can hike the mainland jungles or dive the Blue Hole, an immense underwater cave.