This working observatory at the summit of Mount Wilson in the San Gabriel Mountains is home to one of the world's largest telescopes accessible to the public.
Visitors can tour the observatory every day from 10 a.m. to 4 p.m. from April 1 to Nov. 30. However, to peek through the 60-inch reflecting telescope (measured by the diameter of the mirror that reflects the light from the stars to an eyepiece) you must make a reservation and pay a fee.
Groups no bigger than 25 can reserve the telescope from dawn to 1 a.m. at a cost of $800, or from dawn to dusk for $1,500. For more details, call (626) 440-9016.