We often read of exciting weddings - bungee jumping, center ice, scuba diving, even the roller coaster. Yes, of course it's possible. You can say "I do" anywhere. Though you must always do the formal wedding paperwork (and say "I do " again) on land, with a street address. People simply get confused about the legal parts of the ceremony, and the 'ceremonial' parts.
The official Provincial registry does not (yet) use GPS coordinates for the legal location of your wedding, nor latitude and longitude. That's why you can get married ON a boat, but you have to sign the papers on land at the dock. You can have your ceremony underwater, but you have to do the legal bits on land. We have married people in boats, on rooftops, and on the train, in a special car set up with a SpeakEasy bar. But once we alight from the fun place, we must sit down and do the legal parts at a (non-moving) legal address.
I lose my mind and my lunch on roller coasters, and will NOT marry you on a ride at Canada's wonderland . I have piloted a plane, but decided not to skyjump out of one. It's too hard to HEAR in a helicopter. I love boats, and I like horses (and love Riverdale Farm, for instance!) so canoes are a definite possibility. I like hiking, and would consider remote parts of the Scarborough Bluffs, and hiking trails. But I have friends with Lyme disease, and I won't venture into tick-infested groves. No matter how idyllic.
So - leave something for the honeymoon, in terms of adventure and escape - but plan your wedding elopement in a location with an address, a view, and a minimum of moving parts.
UPDATE: Yes, we had a nice wedding on a Mariposa Cruise Line Yacht in July. We signed the papers while docked, and performed the ceremony at the Island lagoon - then I caught a water taxi and came back to Queen's Quay. A bit windy, and the party boat that crossed our bow during the ceremony was annoying, though everyone yelled "congratulations". But it's an option...
UPDATE: OK - Streetcar wedding! Moving vehicle! You can rent a modern or a vintage streetcar, for about 55 people. Food, but no alcohol. So have a reception afters
Get out and sign papers on the group photo break! This was fun, but you have to rent a loudspeaker amp - you can't use the TTC one.