If it weren’t for Darwin, the Galápagos Islands might have remained in obscurity with their wealth of odd, indigenous, and fearless wildlife. His evolutionary theories helped land the archipelago on the tourist map, but the great scientist missed out on one of the most stunning landscapes of the Galápagos: its underwater realms. The islands, 600 miles (966 kilometers) from the coast of Ecuador, receive both warm and cold currents, with the Antarctic upswelling, sending a smorgasbord of marine nutrients, attracting a gold mine of marine life.
Here divers see penguins next to tropical reef fish, families of sea lions, and the rare red-lipped batfish in the hundreds. Most divers come, however, to see the preponderance of megafauna. During prime viewing season (July to October), divers swim with hundreds of scalloped hammerhead sharks and spot dozens of bus-size whale sharks. (And yes, they're both harmless.) Live-aboard boats are the best mode of transportation, and the Galápagos Aggressor is one of the few that offers both dives and land-based stops. In the morning, passengers spot blue-footed boobies and prehistoric-looking tortoises on these remote islands; by afternoon, they Zen out amid a panoply of sharks, their jagged bodies silhouetted against the glowing blue of the sea beyond.
The Galápagos Aggressor offers seven-night live-aboard boat trips that stop for land visits on three islands and dives off five islands (from $4,495 per person; aggressor.com).