Located in the north west of the crater, Roque de los Muchachos has an International Astrophysical Observatory which was opened in 1985. The Canary Islands have incredibly clear skies and this area is one of the best places on earth for conducting observations of the cosmos.

The observatory has six telescopes in total, including the famous "Herschel" telescope, named after William Herschel. It's an impressive 420 centimetres in diameter and is used mainly for night observations. Once a year, all the lights on the island are turned off at the same time to make certain observations possible.