here's my idea
take a kayak, probably just one of the ones you sit kinda 'on', not a hollow body one
like this:


then, take a recumbent bike:


mount the pedals on top of the front of the kayak, and rig the gears, handlebars, and chain to go to a wheel mounted on the front of the kayak, then attach two small wheels to the back

here's the kicker: attach fins to the spokes of the front wheel at a slight angle, so when in water, pedaling will still make you move

so who's in? we need to start figuring out the best way to tackle this

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