Mr. Palomar Observatory at dusk
Mt Palomar, astrophysics, cosmology

Palomar Observatory

San Diego

High on Palomar Mountain, at an elevation of 5500ft to avoid light pollution, the Palomar Observatory is simply spectacular – as large as Rome’s Pantheon, with a classic design dating from the 1930s. Run by Pasadena’s prestigious California Institute of Technology, it houses five telescopes including the 200-inch Hale Telescope, once the world's largest.

On weekends between April and October, visitors can take guided tours, usually given at 11am and 1:30pm. Tickets are first-come, first-served. Bring a fleece jacket – temperatures inside the observatory hover just above freezing during cooler months.

Call ahead to check road conditions and opening hours before making the long, winding drive here.

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