The Galapagos Islands are an archipelago located in the Pacific Ocean, about 600 miles west of mainland Ecuador. Comprising 13 main islands and numerous smaller islets, they are known for their unique wildlife and diverse ecosystems. The islands were formed by volcanic activity and are home to many species that are not found anywhere else in the world. The Galapagos Islands played a significant role in the development of Charles Darwin's theory of evolution. In 1835, Darwin visited the islands and observed the distinct species of plants and animals, which led him to formulate his ideas about natural selection. Today, the islands are a UNESCO World Heritage site and a popular destination for ecotourism.