1. Cruise the Galápagos Islands, Ecuador

One day you’re watching giant tortoises mate in swirling mists, then you’re nose-to-nose with a seafaring marine iguana, or snorkelling with a group of penguins. As Darwin appreciated, neighbouring islands have sub-species that have developed differently, leading to one of the most important, world-changing discoveries ever known: evolution.

Make it happen: The best way to explore is by boat. Although three- or four-night cruises are available, try to go for a week at least.

More on the Galápagos Islands.