<P> The Darién Gap is a break in the Pan-American Highway consisting of a large swath of undeveloped swampland and forest within Panama's Darién Province in Central America and the northern portion of Colombia's Chocó Department in South America . The gap begins in Yaviza, Panama and ends in Turbo, Colombia, and is 106 km (66 miles) long . Roadbuilding through this area is expensive and the environmental cost is high . Political consensus in favor of road construction has not emerged . </P> <P> The geography of the Darién Gap on the Colombian side is dominated primarily by the river delta of the Atrato River, which creates a flat marshland at least 80 km (50 mi) wide, half of this being swampland . The Serranía del Baudó range extends along Colombia's Pacific coast and extends into Panama . The Panamanian side, in sharp contrast, is a mountainous rainforest, with terrain reaching from 60 m (197 ft) in the valley floors to 1,845 m (6,053 ft) at the tallest peak (Cerro Tacarcuna, in the Serranía del Darién). </P>

Why are there no roads between panama and colombia
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