Bad knees can handle it, but I can't imagine they could handle a wheelchair. The staff are nice and can give you a hand getting up/down ladders and stairs. To be safe I suggest contacting the boat company by phone to confirm the boat configuration hasn't changed. Tours are great. Sites beautiful. And we didn't get off to climb the cliffs and still found it fulfilling .
I do not know about the other islands but for anacapa island requires climbing a ladder and then several stories of stairs
Getting on and off the boat is easy, just walk up a ramp into the boat. No stairs to climb. And there's bench seating at rear of the boat, outside. Also seating at tables inside the boat.
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