“Hale Telescope at Caltech’s Palomar Observatory in San Diego County, California”
The tour of this facility is highly recommended!
They say that American Astronomy took off in the early 20th Century when Charles Pickering discovered women and George Ellery Hale discovered money. Pickering was famous for employing women as computers at the Harvard Observatory, while Hale, who enjoyed a privileged childhood in Chicago, was very successful at inducing large endowments from wealthy businessmen.