The Galápagos Islands, located roughly 600 miles off the coast of Ecuador, remained a closely-guarded natural secret for millions of years. Sometime in the 1800s, pirates and explorers started arriving in the Galápagos Islands. The most famous early visitor was Charles Darwin, a young naturalist who spent 19 days studying the islands' flora and fauna in 1835.
In 1859, Darwin published On the Origin of Species, which introduced his theory of evolution — and the Galápagos Islands — to the world.