Inca Roads and Chasquis
The Incas were magnificent engineers, they built the most elaborate network of roads and bridges of any ancient culture, known as Qhapaq Ñan. The success of its empire was partly due to being able to reach and control each corner of their territory. Inca engineers used and improved roads left by earlier cultures such as the Chimu, Wari and Tiwanaku among others.
The Incas built more than 18,600 miles/30,000 km of paved roads. There were two main roads, both connected the territory north to south extending along the coast and another along the Andes. Both roads were connected by a shorter network of roads. Along the coast they built a 3,000 m/4,830 km road that connected the Gulf of Guayaquil, Ecuador in the north to the Maule River, Chile in the south. The Andean royal road constructed in the highlands extended along the Andes Mountains. It reached Quito, Ecuador in the north, passed through Cajamarca and Cusco and ended near Tucuman, Argentina. The Andean Royal road was over 3,500 miles long, longer than the longest Roman road.
The Incas did not know the wheel and did not have horses either. Most of the transportation was done by foot using llamas to carry goods from one part of the empire to another. Roads were used by messengers or chasquis carrying messages across the empire.
Inca road network extended from north of Quito to south of Santiago
The Incas developed techniques to overcome the difficult territory of the Andes. Many roads crossed high mountains. On steep slopes they built stone steps resembling giant flights of stairs. In desert areas they built low walls to keep the sand from drifting over the road.
Bridges were built all across the empire. They built spectacular suspension bridges or rope bridges using natural fibers. These fibers were woven together creating a rope as long as the desired length of the bridge. Three of these ropes were woven together creating a thicker and longer rope; they would continue braiding the ropes until they had reached the desired width, length and strength. The ropes were then tied together with branches of trees and pieces of wood were added to the floor creating a cable floor of at least four to five feet wide. The finished cable floor was then attached to abutments supporting the ends on each side. They also attached ropes on both sides of the bridge that served as handrails. The last existing Inca suspension bridge is located near Cusco in the town of Huinchiri.
Inca rope bridge
Because the Inca Empire controlled such a vast territory they needed a way to communicate with all the its corners. They set up a network of messengers by which important messages would be conveyed. These messengers were known as Chasquis and were chosen from the strongest and fittest male youngsters. They ran many miles a day to relay messages. They lived in cabins or tambos along the roads usually in groups of four or six. When a chasqui was spotted, another one would run to meet him. He would run beside the incoming messenger trying to listen and to memorize the message, he would also relay the quipu if he was carrying one. The tired chasqui would stay and rest in the cabin while the other one will run to the next relay station. In this way messages could travel over 250 miles a day.
Chasquis were chosen from the strongest and fittest males
In case of an invasion or a rebellion an emergency message was sent through a chain of bonfires. As each group of chasquis saw the smoke they would lit a bonfire that could be seen by the next cabin or tambo. The Sapa Inca would send his army toward the bonfire before the cause was known, usually on his way he would meet a messenger and learn from him the exact nature of the emergency.
Archeological findings show that some tambos or relay stations were more elaborate than others. They were probably used as a place for officials or the Sapa Inca to stay during their traveling across the empire.