Paranal Observatory is ESO’s flagship optical observatory at 2635 metres in Chile’s Atacama Desert, home to the Very Large Telescope (VLT) and its interferometer, VISTA, and the VLT Survey Telescope. Free guided tours run every Saturday at 10:00 and 14:00, with compulsory online registration, ID/QR check, release form and health declaration. Visitors park outside and use the tour bus; there is no visitor accommodation or on-site food, and tours can be cancelled for severe weather. Check ESO’s visitor page for current booking and safety requirements.