You will find wonders aplenty. And because it is a very active working observatory, every moment you spend there will be richly rewarded.

(I've been to visit a few times!)

Lowell Observatory has strong historical associations. You can visit Percival Lowell's 24-inch refractor in its wedding-cake dome, once floated on salt water and turned by pulling on ropes for a distinctly nautical feel. Even his tomb evokes the sky and the observatory. Not only the telescope, but the photographic plates, used to discover Pluto, are on display. And reaching for more light, the Perkins Observatory 1.8-m reflector (shared currently with Ohio Wesleyan University) has been relocated from Ohio to Anderson Mesa, just south of Flagstaff. Anderson Mesa also hosts the Naval Prototype Optical Interferometer (NPOI) and the National Undergraduate Research Observatory (NURO). The Lowell headquarters in Flagstaff is well worth a visit, especially with the new visitor center. The dome of the old library (sadly, I'm not sure it's still open to visitors) is a work of art, with the large painting of Lowell and the history of Mars exploration and a huge stained-glass Saturn lamp overhead. One can see one of the original discovery plates of Pluto, and on public nights look through the classic refractor (I couldn't find any canals painted into the eyepiece). And if you've gotten this far, you can't pass up visits to Meteor Crater, Sunset Crater, and the Wupatki ruins.

Learn More:

Lowell Observatory Website

Cheers, BR Felix