The islands' geographic isolation, over 960km (600 miles) off the continental coast, has led to the evolution of numerous endemic species here. This, combined with the animals' fearlessness of humans, played a key role in Charles Darwin's development of the theory of natural selection.
Nearly every visitor to the Galápagos arrives by plane, and only two airlines make the flight from the mainland. Seats are often booked solid far in advance, and fares are certainly not cheap. The best way to see the islands is to book a package tour out of Quito or Guayaquil. Most packages will include airfare and a berth on a local cruise ship, or a planned land-based itinerary. The ships that tour the islands vary widely in size and quality. My advice: Spend as much money as you can afford. But no matter what you can pay, you won't be disappointed. The wildlife here, which so beguiled Charles Darwin and Herman Melville in the 19th century, is no less astonishing now than it was when they visited.
The Galápagos Islands were formed over 5 million years ago by volcanic eruptions. These (and the ongoing formation and development of the islands) occur primarily over a relatively localized hot spot. However, due to continental drift, the islands are slowly but steadily migrating eastward. Today, the most active islands are Fernandina and Isabela, the westernmost islands, although several others have ongoing volcanic activity.
The first European to discover the Galápagos Islands was the Spanish priest Father Tomás de Berlanga, who landed here in 1535. In the centuries that followed, the islands were frequented by various settlers, pirates, fishermen, and whalers. Today only five of the islands are populated -- Santa Cruz, San Cristóbal, Floreana, Isabela, and Baltra.