Darien Gap is a break in the Pan-American Highway with a length of 60 miles (96 km) without roads. It makes that overland travel across Central America is pretty much impossible. This gap has been successfully crossed a handful of times -usually by expeditions equipped with off-road vehicles and staffed by special forces types, a near-impenetrable jungle that guerrilla fighters and drug runners call home.
Located in the Putumayo Department of Colombia, the road from Mocoa to San Francisco is one of the most dangerous roads in the world. It was built in 1930 and zigzags the Andean mountain range. There have been numerous deaths from cars falling off.