Tours
When the new Allegheny Observatory was designed it was done so with the public in mind, the floor plan included a lecture hall. When the new facility first went into operation, on every clear evening it was opened for the public to look through the 13" telescope but if it were a cloudy night "they would be given an illustrated lecture on astronomy." John Brashear once said "the Allegheny observatory would remain forever free to the people" and to this day it has although in modern times the free public tours are only offered a couple nights each week.
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