We visited about a week ago. I called over in the morning to ask about a wheelchair accessible tour. We were lucky and they had a giude available for a modified tour. It was GREAT! Our guide, Carol, was wonderful. I highly recommend.
They will accommodate for anyone handicapped
There are ramps outside of the biosphere but the inside is not accessible by wheelchair
I didn't ask about accommodation, but there are lots of stairs and difficult passages that would be challenging for handicapped people.
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