The hook
For twenty-six years the largest telescope on Earth sat on a mountain in the back country of San Diego County, and you can still drive up and stand under it.
01Why it's worth it
George Ellery Hale, the man who built the great telescope on Mount Wilson, spent the end of his life building a bigger one, a two-hundred-inch reflector he sited on Palomar Mountain to get above the lights of Los Angeles. It took decades and survived a world war, and when it saw first light in 1949, under the eye of Edwin Hubble, it was the largest telescope in the world, and stayed that way until 1975. The Hale Telescope is still doing working science today, seventy-five years on. The white dome is enormous and strangely beautiful, the drive up the mountain through pine forest is half the pleasure, and inside you look up at a machine that redrew the sky.
02How to experience it
It's on Palomar Mountain in the north county backcountry, about eight hours from the Bay and a long climb up a winding road. Self-guided visits to the dome run daily; guided tours are weekends in the warmer months. There's a small museum. Bring a layer since it's high and cool, and make a day of the mountain.