Cuba is probably the most famous country Americans were not allowed to visit as tourists. Since the restrictions were loosened over two years ago, it is becoming a hot spot for adventurers. Cave diving in the country is superb – you can’t dive and explore the depths of a cave that reaches 70-feet deep in many places. Scuba diving and zip lining are popular, too. Sign up for the Havana Marathon, go rock climbing, and visit in time for carnivals, which are usually in the summer.