1. Great Barrier Reef, Australia
After circumnavigating this massive continent for a mix of thriving cities, golden beaches, and outback outpost, you can see the highlight: a diving or snorkeling tour of the biggest reef in the world. Swim alongside tropical fish and coral, and if you're lucky you'll get a glimpse of the dugong (sea cow) or the near-extinct large green turtle.
After circumnavigating this massive continent for a mix of thriving cities, golden beaches, and outback outpost, you can see the highlight: a diving or snorkeling tour of the biggest reef in the world. Swim alongside tropical fish and coral, and if you're lucky you'll get a glimpse of the dugong (sea cow) or the near-extinct large green turtle.
Photo: Great Barrier Reef
/ iStock.com / Pete Niesen