The lower level of the fort is accessible by wheelchair but the slope on the Sally port can be a bit of a doozy so be prepared for that. There is also a paved trail that goes from the parking lot, around Battery Hambright to the North Pier and back. The Visitor Center has access ramps and power assisted doors too!
Most parts are, I took my Father there about a month ago, he's on a scooter, honestly I think his wheel chair would have been easier to navigate around the fort
All of the place is except for the top level of the fort you have to climb stairs but it's honestly just a mirror of the bottom so you won't be missing much
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