I can't really help - but the Batobus website should have the information you need. There is a ramp onto the boat but you'll need to get up and down steps on the riverside at several of the stops
At the Marias there was a rather steep ramp, but it was accessible
There are many steps leading down to various stops. There is information on the site about the Eiffel Tower stop that has a ramp.
I would search Batobus for info. It didn’t look possible in many of the stops I used.
There is a ramp to the boat, yes, but I do not recall if there were any modifications to the couple of stairs once on the boat. I’m sorry, I’m not entirely sure!
Depending what you are looking for, just a heads up: this was strictly a water taxi. It was beautiful and a fun way to see the city from a different angle, but we thought there would be a little bit more of a tour or some fun facts. Just so you know!
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