There are stairs to enter & exit but I believe there is a handicapped accessible elevator. The bulk of the caverns floor is covered in driveway gravel which might be awkward w a wslker, there are a few ramps, and a few narrow passes where you may need to hold an elbow instead of the walker. You should call them. The owners are quite nice & will really be able to give the best advice.
The stairs are tough... and the passage is narrow at times
There are stairs but it is steep and 79 stairs.
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