Why not get married on a lake that abuts the BWCA, allowing guests to stay in lodges, or whatever, then after the outdoor ceremony, and when the party is over, you and your dearly-beloved jump in a canoe and paddle off into the wilderness...way better than a car with a bunch of cans tied to the back.  You could even have a tent set up on the other side of the lake waiting for you.

My wife and I were married in a conventional church, but then spent the next 2 weeks backpacking in Zion National Park...great memories.

Good luck.

prouboy