It's no coincidence that the word "muse" appears in "museum!" Underground Gold Miners Museum aims to inspire, educate and entertain its visitors, so add it to your itinerary.
You're spoiled for sightseeing choice when in Alleghany. Underground Gold Miners Museum is a great place to start here, but there are plenty of other worthwhile places to experience. Chimney Rock/Empire Creek Trails, and Downieville Museum are near the museum and and will cap off your day nicely.