The Inca Empire and its hanging bridges

Around 1531 the Spanish forces commanded by Francisco Pizarro disembarked on the coast of Peru, thus initiating the long journey through the immense Inca territory. Advancing among the Andean mountains, the Spaniards could not help but marvel at the complexity of the Empire and the sophistication of the immense road network built and maintained by the Incas.

The Incas built innumerable bridges along their road network in order to overcome many of the deep rivers that cross the Andes. Where the rivers were too wide to be crossed with the help of wooden poles, the Incas devised the construction of hanging bridges, which were made up of vegetables and fibers. The largest suspension bridges that are known represent one of the most important engineering achievements achieved by the Incas.

Construction technology of bridges

The ways of passage

The passageways in the fiber bridges were constructed with a series of cables arranged at ground level, between the two towers located on each side of the river. Like the side cables, these were tensioned and secured to anchors, but then these were joined together by rope trusses. In larger suspension bridges, there were also tie rods, arranged perpendicular to the cables, thus obtaining a wider and safer floor for the passageway. The mats were used for the preservation of the cables in front of the continuous traffic so that they give greater security in the displacements, allowing even the animals that the Incas used to move through these bridges.

Construction and repair of bridges

In the Inca Empire, bridges were built and maintained through a labor system organized in shifts. The communities around the bridge were assigned the obligation to maintain and replace the cables or even the entire bridge if necessary. Several Spanish chroniclers point out that the largest bridge in the empire had to be completely repaired once every two years. Fun facts