There are actually two museums here. The first is the Fremont County Pioneer Museum which is the main large building with many interesting exhibits. Its hours are April-September: 9AM-5PM; October-March: 10AM-4PM. FREE ADMISSION!!! The cache is located in the museum but the other museum!
The second museum is The Museum of the American West which comprises many of the old historical buildings and Pioneer Village. The Village buildings are open May17-Oct 31: Mon-Sat, 9AM-4PM. Its main office is open year round Monday-Friday, 9AM-4PM. FREE ADMISSION!!!!