Travelling from Arequipa to the Valle de los Volcanes in southern Peru is an experience in itself. The road passes through flat desert areas, deep canyons and fertile river oases, and finally reaches high-altitude villages. After a nine-hour truck ride, we arrived in Chachas, a small village nestled in the foothills of the Cordillera Chila mountain range. We stayed in a rural guesthouse nearby, using it as our base camp to rest and organise our field equipment.
The next day, with our equipment ready, we took a dirt track to our field study site in the Cordillera Chila mountain range. After a few hours, we reached an altitude of 5,000 metres. From there, we began our ascent to the San Félix rock glacier, taking it slowly to allow our bodies to adjust to the altitude. On this rock glacier system, which is connected to a wetland, the team took vegetation samples, installed a GPS base station and conducted drone surveys of the rock glacier. After a long day’s work at an altitude of 5,600 metres, we returned to the dirt track to meet our truck driver and head back to Chachas. We returned to our base camp, organised our equipment, and prepared for the next day.
The next day, we drove to the Coropuna volcano (6,405 metres). At an altitude of around 5,000 metres, we left the truck and started walking towards the rock glaciers located on the southern side of the volcano. Here, the group took snow samples for chemical analysis and conducted vegetation plot surveys. Two drones were flown up to an altitude of between 5,900 and 5,500 metres in order to capture detailed images of two active rock glaciers.
After working at high altitudes for several days, we returned to Arequipa and took a day to recover. Our final mission was to reach the iconic volcanic complex of Chachani, visible from Arequipa. After navigating a challenging route along a dirt track for several hours, we successfully located a pass at an elevation of 5,100 metres above sea level, positioned between the Chachani and Nocarane volcanoes. From there, we continued on foot to observe the vibrantly coloured rock glaciers of the Nocarane volcano (5,787 metres). These remarkable rock glaciers exhibit distinctive colouration resulting from weathering and geological processes associated with the Nocarane volcanism.
The expedition concluded in the city of Arequipa, where all the group members organised their materials and prepared to return home. The collaboration with local researchers from Huaraz proved to be a success. It underlined the importance of local knowledge when conducting research in the high Andes, ensuring a smooth and trouble-free process.
Sebastián Vivero is a drone specialist at the Laboratory of Catchment Hydrology and Geomorphology (CHANGE) at the Swiss Federal Institute of Technology (EPFL) in Lausanne. His field trip took place in autumn 2025 with financial support from a Polar Access Fund.