Peru, a country with a rich historical heritage, has added drones to archaeology's classical tools for surveying, registering and protecting archaeological sites from climate- and human-caused damage.

The use of unmanned aerial vehicles, or drones, has so far helped in registering 375 archaeological sites, or 63.5 percent of those in the Lima metropolitan area, and most of them are located among buildings and avenues in the city of more than 9 million people.

While a drone hovers above a pre-Columbian truncated pyramid in the Lima district of San Borja, the project coordinator at the Culture Ministry, Aldo Watanave, described for EFE how difficult it was to develop a registry of archaeological sites before the arrival of drones.

"Back then, to obtain aerial images, we had to check records of aerial photography from the 1950s, 1960s and 1970s, or we were required to wait until a satellite orbited over a specific area and took a picture," Watanave said.

Watanave recalled the long hours of work required to prepare scale and 3D maps of an archaeological site on the ministry's equipment.

Almost three years into the program, there are already nine drones that the archaeology team can use to register sites, a job that continues on a day-to-day basis.

The fleet consists of four octocopter drones (eight propellers) used to take photos and five quadcopters (four propellers) used to shoot video.

The workload has been reduced by the drones and now a single expert can operate the device's controls while a co-worker controls altitude and speed via a screen.

Where the traditional method for producing a map might take two to three days in the past, "now it can be done in a matter of minutes," Watanave said.

In Cajamarquilla, built in A.D. 600-730 and the largest adobe citadel on Peru's central coast, drones detected trash dumps on the roadsides.

As efforts continue to preserve Peru's architectural heritage, drones are allowing the detection of damage caused by people who enter archaeological areas illegally and the adoption of preventive measures in the face of climate events, such as "El Niño."