Sorry it took so long to get back to you!
We do have an indoor pool which is available to guests between the hours of 8:00am - 11:00pm. There are pictures available on our Trip Advisor Page as well as our Cumberland Inn Website.
It is a little hard to find and from the outside looks like a greenhouse rather than a pool. It's opposite the parking lot from the museum, on the end of the building.
It has a very nice pool that is clean.
Get an answer from Cumberland Inn and Museum staff and past guests.