The Big Bear Solar Observatory is operated by the New Jersey Institute of Technology. Their newest solar telescope has a 1.6 meter clear aperture and is the largest aperture solar telescope in the world. Tours are offered from 2-3pm on the 2nd and 4th Tuesdays of the month. I love the stark whiteness of the building against the blue and green of its surroundings.
Links: BBSO (tour info, webcams, latest images)
