I would say yes, there were 2 RV's on the ferry with us when we went to Madeline island. When we went to big bay park there were a few RV's going into the park.
I did have an RV on the ferry over to Madeleine Island. Also a semi-trailer. I don't now what limits may be in place.
When I was there I did not see any. Also I do not know if the ferry that takes your over would allow an RV to cross. Probably would depend on how long the RV is.
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