Built in the 1930s by Paraguayan prisoners during the Chaco War, at places it was cut into the steep cliff side. One side of the road is solid rock, the other falls off into a 600-meter abyss.
Most of the road is only 3.5 meters wide, and some sections are unpaved, without guardrails.
Warm and humid winds from the Amazon hit upon the eastern slopes of Andes bringing heavy rains and fog drenching the already dangerous road in torrents of water.
hit upon
torrents
There are numerous mudslides and tumbling rocks, and small waterfalls occasionally rain down from the cliff sides.