La Palma, Spain
Spain's Canary Islands take great pride in their astronomy-friendly atmospheric conditions—so much so that they have laws, nicknamed "Sky Laws," to preserve the excellent sky quality. As a result, more than 60 scientific institutions from 17 different countries have come to observe at the fleet of telescopes stationed there—one of the most extensive in the world. The Observatorio del Roque de los Muchachos, perched on the edge of a caldera nearly 8,000 feet above sea level, is home to many sophisticated telescopes, including the Swedish 1-m Solar Telescope, the largest solar telescope in Europe.
Visit: Tours take place on Tuesdays, Fridays, Saturdays, and Sundays and must be booked in advance online.
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