The Galápagos Islands are a chain of islands, or archipelago, in the eastern Pacific Ocean. They are part of the country of Ecuador, in South America. The Galápagos lie about 966 kilometers (600 miles) off of the Ecuadorian coast. 

There are thirteen major islands and a handful of smaller islands that make up the Galápagos archipelago. The largest of the islands is called Isabela. It is approximately 129 kilometers (80 miles) long. Repeated volcanic eruptions helped to form the rugged mountain landscape of the Galápagos Islands.