Very Large Telescope (VLT) at the European Southern Observatory's (ESO) site at Cerro Paranal in Chile. The VLT comprises four 8.2-metre mirror telescopes (Antu, Kueyen, Melipal and Yepun), housed in the buildings seen. They provide images which are combined by interferometry. This gives an image equivalent to that obtained by a 16-metre diameter mirror, making the VLT one of the most powerful telescopes in the world. The mirrors are flexible, and are constantly adjusted by computers to compensate for errors. Cerro Paranal has an altitude of 2600 metres and is situated in the Atacama Desert, one of the driest places on Earth. This gives the site excellent viewing conditions.