They first started climbing down with ropes that hung from the Sibillini Mountains. But the chances of being crushed by falling rocks quickly became too great, even for them, who knew the mountains like the backs of their hands. So the men of the Alpine Rescue of Marche left their ropes and pickaxes in their trucks and turned to remote controls. Drones would have to do their work instead.

In 2016, central Italy was shocked by strong earthquakes. A 6.5 magnitude quake that hit in October was the strongest Italy had seen since 1980. Towns in the area are stuck between rocky slopes. Even though Rome is only 150 kilometers away, this is one of the most arduous places to reach in the country. The massive quakes revealed the fragility of the mountains and triggered dozens of landslides and rockslides that still threaten people, roads, and businesses.

The fragile landscape needs to be monitored as closely as possible to prevent further damage. That's why some volunteers of the Alpine Rescue, led by pugnacious geologist Gianni Scalella, are flying over 2500 square kilometers using drones. Several other drone pilots make up the team (one works for Italian Civil Protection, others are freelance engineers and surveyors). In total, Scalella has a dozen volunteers and six drones.

This is what the drones are able to see from their vantage point:

The project, dubbed "Rocky Walls Monitoring" started in September 2016 and was "institutionalized" almost three months later when the Marche Region—the most damaged by the earthquakes together with the Umbria and Lazio regions—officially appointed the geologist and his volunteers to monitor it.

"But our work keeps being for free. The Region only refunds us the cost of the DVDs we use to upload the video footage," Scalella explained to Motherboard while driving along the hairpin turns that connect Acquasanta Terme and Pescara del Tronto, an area which was totally devastated by a major earthquake in August last year.

Landslides and rockslides can still happen at any moment—Scalella's drone operators constantly risk being crushed by falling rocks. That's why the Alpine rescue "stuntmen" don't climb down with ropes anymore. Using a helicopter could be an option, but the airflow caused by its propellers may also trigger new rockslides.

"Drones are easier to use—as soon as the wind goes down or we spot a ray of sunshine we can make them take off. Helicopters need to be reserved and don't take off if the weather is unstable" explained Giancarlo Guglielmi, a 67-year old retired teacher who is now the regional delegate of the Alpine Rescue of Marche.

"Our work starts with an emergency call: if drones detect a risk for a town or a road we call Civil Protection. We show them the footage, then they work to secure the area," Scalella explained.

The volunteers live in a region called Marche, which has been shocked by earthquakes in recent years. Very often, they're already aware of which rocky walls are the most unstable. Sometimes regional mayors suggest where the drones should look, while other warnings come from citizens and business owners.

"We fulfill every request: we just need to get the equipment and we're ready" Scalella said. A couple of weeks ago, a drone survey allowed several shops to reopen. Aerial images showed there was no longer any hydrogeological instability threatening them.

Currently, most of Scalella and his volunteers' work is focused on the highest peak of Marche. A rockslide on Monte Vettore is the most alarming situation at the moment. Vettore, which is 2,476 meters high, is the second highest peak in the Apennines, the mountain chain that stretches down through mainland Italy. Last January, more than 30,000 meters of cubic rock broke off the east side of the mountain, and fell 1900 meters.

A photo of the rockslide that broke off from Monte Vettore. Image: Gianni Scalella

"The rockslide wiped down a forest and an important road," Scalella said. "That road leads to a water source that supplies 10,000 people. In this moment, there's a 45 meter high rock in a precarious balance. That rock could cause more damages—geological danger is very high over there."

Rockslides also threaten people at home. "There are many homes at risk in Visso and Pievetorina [two villages hit by the earthquakes] as they were built some years ago at the bottom of rocky walls. In that period it was quite easy to get a building permit even in overtly risky areas," Scalella said.