Billie - The Center is on the slope of Spencer Butte and quite steep in places. Even where we have switchbacks, there are shallow steps. Someone in a wheel chair could see a few enclosures/birds at the top of the driveway but that would be about it. We're working on it, but it will take a lot of money and some time.The terrain is simply challenging.
There are several steps also.
I'm afraid I don't think that it will be safe for someone in a wheelchair. When I visited the birds I recently had knee surgery, I did it but had difficulty in some areas. Maybe you can take pictures and share them with your friend.
It's pretty tough terrain for a wheelchair and the paths between the cages are dirt and gravel so it would be tough to navigate it by yourself.
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