Inca bridge
Terraces – Flickr – pellaea

What’s the problem?
The Bridge at Q’eswachaka (video 3:15) – Every year, local communities on either side of the Apurimac River Canyon use traditional Inka engineering techniques to rebuild the Q’eswachaka Bridge. The entire bridge is built in only three days. The bridge has been rebuilt in this same location continually since the time of the Inka. )