I'm not sure of true elevation. Are you asking because of the walking involved?
It would be about the same as Tucson. It is just north of there. It is in a hollow ( valley) with hills around it. I'd say 100 + steps down to it and 100 + steps up to level parking lot. Tucson is 2350 ft approximately. So Biosphere 2 would be maybe 2,500 ft.
Best to ask google.
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