Everyone's partially right. The Darien Gap IS possible, there is no "route" and your odds of getting through alive today are slim.
The "route" has been done exactly twice, I read the book by the first guy to do it on a bike, Ed Culberson, (get his book on our books pages - "Obsessions die hard") and know the second, Helge Pedersen, and he wouldn't consider doing it again, even disregarding the main deterrent today - guerilleras, drug smugglers, and bandits in general.
The whole area is a heavy drug area, and is considered very dangerous. The Panama military won't even go in there.
The area itself is your worst nightmare jungle. Helge tells of wading through swamps up to his neck, pushing the bike in a tiny dugout canoe, covered with leeches all over his body, watching snakes slither by, then winching the bike up steep jungle hills and slashing a trail with a machete. Total mileage on the bike's odometer after the whole 50 mile stretch - 2. The rest was carried or dragged. And it took two guys, one bike, two weeks.
The best is to fly from Bogota, Lima, or Quito, to Panama. Quito can be difficult due to small plane size. Going south, do not fly to Ecuador unless you have a carnet.
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