Travel

when on the road, truck stops have them available for a modest fee (or so I am told).

The major national health clubs often allow out-of-town or new potential members to get a guest pass to try out their facilities. If you are willing to go with what that entails (a marketing pitch if you present as a new potential member), that would gain you access as well as a work-out. And if, by chance, you have a membership, you could plot out their locations ahead of time.