In 2025, archaeologists mapped an Inca tunnel beneath Cusco and revived a centuries-old legend

When strolling through Cusco, it can feel as if the city’s story has already been fully told. Stone walls, broad plazas, and narrow alleys seem to tell the story of the Inca Empire. Indeed, for centuries, people believed that what was visible aboveground was everything left from this ancient civilization.

But, lately, specialists started searching deeper beneath the soil, and found something really astonishing. As it appears, the old capital of the Incas hides a huge underground world beneath our feet. It is not just a single abandoned tunnel beneath the city.Discovering an underground city using radarFinding out what lies beneath a modern city is extremely challenging. Obviously, digging up the entire city will not provide any results. That is why modern technology is so vital for history and archaeology. Modern scientists use some special devices to scan soil without digging holes in the ground. As a result of a recent study indexed on PubMed, it was stated that researchers managed to discover a hidden subterranean city in the Plaza de Armas, the central square of Cusco.

Using radar technology, researchers created a map showing the structure of the layers underneath the soil. The research suggests that soil can preserve a record of past activity. Thus, one can say that radar technology can be used for discovering and studying hidden objects.

The Inca were excellent underground architectsThe uncovering of objects hidden beneath Cusco is quite logical considering the typical approach to building used by the Inca. These were excellent architects and builders who not only constructed stone walls and terrace farms but were equally interested in what was happening underground. As mentioned in a 2023 peer-reviewed article on Scientific Reports, the Inca managed to create intricate subsurface systems that helped to drain away water and hide special water channels underground.

The article provides physical evidence of a tunnel that carried water directly into the temple. The use of such techniques in well-known structures makes it natural to expect the same from a capital city. Water management, secret passages, and drainage systems were common practices for these ancient people who felt quite confident while forming underground spaces for their cities.What this means for our historyThis discovery may change how we think about Cusco. Historically, the old capital was considered nothing more than an architectural masterpiece – an artifact that had been preserved until our day and studied exclusively based on the visible part of its walls.

Now, however, it is obvious that Cusco was never just an old monument – but rather an actively operating archaeological site. As it turned out, the Incas designed their own capital as a multi-layer structure, which existed above and beneath the soil surface.

The new construction that occurred when colonial and modern constructions were placed on top of the ruins throughout the centuries did not destroy the old layers, but simply concealed them.

This allows us to see Cusco as a fully operational city with its rich historical layers.This subterranean network makes Cusco seem even more complex and mysterious. Cusco is not only an archaeological site but an extraordinary engineering masterpiece whose secrets are far from being revealed yet. Today, we can see that Inca history extended below street level as well. Instead, there were many other layers of their lives underground. Although our knowledge of the specifics of this intricate system is currently limited, there are certain things we can be sure of today.

Cusco appears to have been a multilayered city, though many details remain unknown.