Inca Road System - 25,000 Miles of Road Connecting the Inca Empire

Traveling the Inca Empire on the Inca Road

Modern Traveler on the Inca Road to Choquequirao
Modern Traveler on the Inca Road to Choquequirao. Alex Robinson / Creative / Getty Images

The Inca Road (called Capaq Ñan or Qhapaq Ñan in the Inca language 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 their empire.

The construction exploited and expanded on existing ancient roadways, and it ended abruptly 125 years later when the Spanish arrived in Peru. In contrast, the Roman Empire's road system, also built on existing roadways, included twice as many miles of road, but it took them 600 years to build.

Four Roads from Cuzco

The Inca road system runs the entire length of Peru and beyond, from Ecuador to Chile and northern Argentina, a straight-line distance of some 3,200 km (2,000 mi). The heart of the road system is at Cuzco, the political heart and capital of the Inca Empire. All the main roads radiated out from Cuzco, each named for and pointed in the cardinal directions away from Cuzco.

  • 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 Cuzco to Quito was the most important of these four, keeping the rulers of the empire in close touch with their lands and subject people 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 or alpacas 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 desert stretches included the making of oases and wells by low walls or cairns.

    Practical Concerns

    The roads were primarily built for practicality, and they were intended to move people, goods, and armies quickly and safely across the length and breadth of the empire. 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 inter-mountain valleys and across plateaus. The roads skirted much of the inhospitable South American desert coast, running instead inland along the Andean foothills where sources of water could be found. Marshy areas were avoided where possible.

    Architectural innovations along the trail where difficulties could not be avoided included drainage systems of gutters and culverts, switchbacks, bridge spans, and in many places low walls built to bracket the road and protect it from erosion. In some places,  tunnels and retaining walls were built to allow safe navigation.

    The Atacama Desert

    Precolumbian travel across Chile's Atacama desert could not be avoided, however. In the 16th century, the Contact-period Spanish historian Gonzalo Fernandez de Oviedo crossed the desert using the Inca Road. He describes having to break his people into small groups to share and carry food and water supplies. He also sent horsemen ahead to identify the location of the next available water source.

    Chilean archaeologist Luis Briones has argued that the famed Atacama geoglyphs carved into the desert pavement and on the Andean foothills were markers indicating where water sources, salt flats, and animal fodder could be found.

    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. Accordingly, placed along the road at every 20-22 km were tambos or tampu, small building clusters or villages which acted as rest stops. These way stations provided lodging, food, and supplies for travelers, as well as opportunities for trading with local businesses.

    Several small facilities were kept as storage spaces to support tampu, of many different sizes. Royal officials called tocricoc were in charge of the cleanliness and maintenance of the roads; but a constant presence that could not be stamped out were pomaranra, road thieves or bandits.

    Carrying the Mail

    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 [ruled 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) each day.

    American packaging researcher Zachary Frenzel (2017) studied methods used by Incan travelers as illustrated by Spanish chroniclers. People on the trails used rope bundles, cloth sacks, or large clay pots known as aribalos to carry goods.

    The aribalos were likely used for the movement of chicha beer, a maize-based mildly alcoholic beverage that was an important element of elite Inca rituals. Frenzel found that traffic continued on the road after the Spanish arrived in the same manner, except for the addition of wooden trunks and leather bota bags for carrying liquids.

    Non-State Uses

    Chilean archaeologist Francisco Garrido (2016, 2017) has argued that the Inca Road also served as a traffic route for "bottom-up" entrepreneurs. Garcilaso de la Vega stated unequivocally that commoners were not permitted to use the roads unless they had been sent to run errands by the Inca rulers or their local chiefs.

    However, was that ever a practical reality of policing 40,000 km? Garrido surveyed a portion of the Inca Road itself and other nearby archaeological sites in the Atacama desert in Chile, and found that the roads were used by the miners to circulate mining and other craft products on the road and to funnel off-road traffic to and from the local mining camps.

    Interestingly, a group of economists led by Christian Volpe (2017) studied the effects of modern expansions on the Inca road system, and suggest that in modern times, improvements in transport infrastructure have had a significant positive impact on various companies' exports and job growth.

    Sources

    Hiking the section of the Inca Road leading to Machu Picchu is a popular tourist experience.