The Inca road system (called Capaq Ñan in Quechua and Gran Ruta Inca in Spanish) was an essential part of the success of the Inca Empire. The road system included an astounding 40,000 kilometers (25,000 miles) of roads, bridges, tunnels and causeways. Road construction began in the mid-fifteenth century when the Inca gained control over its neighbors and started expanding its empire; it ended abruptly 125 years later when the Spanish arrived in Peru. As a contrast, the Roman Empire built twice as many miles of road, but it took them 600 years.
Four Roads from Cuzco
The Inca road system runs the entire length of Peru and beyond, from Ecuador to Chile and northern Argentina, a straightline distance of some 3,200 km (2,000 mi). The heart of the road system is at Cuzco, also the heart and capital of the Inca Empire, and from Cuzco, four main roads radiated out in the cardinal directions.
- Chinchaysuyu, headed to the north and ending in Quito, Ecuador
- Cuntisuyu, to the west and to the Pacific coast
- Collasuyu, led southward, ending in Chile and northern Argentina
- Antisuyu, eastward to the western edge of the Amazon jungle
According to historical records, the Chinchaysuyu road from Quito to Cuzco was the most important, connecting the rulers of the empire in close touch with their lands in the north.
Inca Road Construction
Since wheeled vehicles were unknown to the Inca, the surfaces of the Inca Road were intended for foot traffic, accompanied by llamas as pack animals. Some of the roadways were paved with stone cobbles, but many others were natural dirt pathways between 1-4 meters (3.5-15 feet) in width. The roads were primarily built along straight lines, with only a rare deflection by no more than 20 degrees within a 5 km (3 mi) stretch. In the highlands, the roads were constructed to avoid major curves.
To traverse the mountainous regions the Inca built long stairways and switchbacks; for lowland roads through marshes and wetlands they built causeways; crossing rivers and streams required bridges and culverts; and roads between desert oases were marked by low walls or cairns.
But, in the main, the roads were also built for practicality, intended to move people, goods and armies quickly and safely across the length and breadth of the empire. The roads were built along some segments constructed centuries earlier by conquered societies. The Inca almost always kept the road below an altitude of 5,000 meters (16,400 feet), and where at all possible they followed flat intermountain valleys and across plateaus. The roads skirted much of the unhospitable South American desert coast, instead running inland along the foothills where sources of water could be found; and marshy areas too were avoided.
Architectural innovations along the trail where difficulties could not be avoided included drainages through gutters and culverts, and in many places low walls built to delimit the road. In some places tunnels and retaining walls were built to allow safe navigation.
Lodging Along the Inca Road
According to 16th century historical writers such as Inca Garcilaso de la Vega, people walked the Inca road at the rate of about 20-22 km (~12-14 mi) a day; and accordingly, placed along the road at every 20-22 km were tampu, small building clusters or villages which acted as rest stops or way stations, providing lodging, food, and supplies for travelers and opportunities for trading with local businesses.
A postal system was an essential part of the Inca Road, with relay runners called chasqui stationed along the road at 1.4 km (.8 mi) intervals. Information was taken along the road either verbally or stored in the Inca writing systems of knotted strings called quipu. In special circumstances, exotic goods could be carried by the chasqui: it was reported that the ruler Topa Inca [rled 1471-1493] could dine in Cuzco on two-day-old fish brought in from the coast, a travel rate of about 240 km (150 mi) a day.
- Be sure to see the Inca Road Photo Essay for a glimpse at the marvelous bridges, tunnels and waystations
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