One of the largest and most active volcanoes located on Isabela Island in the Galapagos Islands, Sierra Negra is a shield volcano characterised by a massive oval crater that measures 9km east-west and 7km north-south. The volcano has a history of at least 10 eruptions, with a resting period of 15 years on average. Visitors can enjoy a 5-6 hour hike to its enormous crater and take in the native fauna and flora as well as the breathtaking landscape.