Boticas, Portugal, June 29, 2025 (Lusa) - Archaeologists are mapping the hill forts of Barroso, between Boticas and Montalegre, using non-invasive methods such as ground-penetrating radar, magnetometers and drones. The project also includes virtual reconstructions, an online atlas, a documentary and tourist routes.
The project “Ativar - Local communities and the origins of the agricultural landscape of Barroso” aims to help people learn about the history of the World Agricultural Heritage Site, which covers Boticas and Montalegre in the north of the district of Vila Real. More than 50 castros are scattered arpund this area.
“The main objective, ultimately, is to socially activate a heritage that we have largely overlooked, namely the castros,” archaeologist João Fonte told the Lusa news agency.
He views this important historical and monumental legacy as one that “may lie in the remote origins” of this World Agricultural Heritage Site, classified in 2018.
Researchers were in the field this week collecting data, and the Lusa news agency followed the work at the Carvalhelhos hill fort in Boticas, which people occupied from the Iron Age to Roman times.
At this hill fort, visitors can see a defensive system consisting of two lines of walls, two large moats and a field of embedded stones. The interior platforms still contain the remains of circular and rectangular buildings.
João Fonte explained that researchers carry out non-invasive mapping of this historical heritage, i.e., they map it without excavations, and they combine different techniques for this purpose, including ground-penetrating radar, magnetometers, drones, and Lidar technology.
Lidar, whose data is provided by the Directorate-General for Territory (DGT), performs an aerial scan (using a sensor placed on an aircraft), virtually removing vegetation and allowing walls or moats to be identified.
“We are also conducting surveys with dedicated drones in the most complex sites,” he pointed out.
Then, using geophysical techniques such as georadar and magnetometers, we can map buried structures.
“By combining this data, we will then reconstruct some of these castros in three dimensions,” added João Fonte.
Tiago do Pereiro, an archaeologist specialising in geophysics, was responsible for operating the magnetometer, an equipment with five sensors attached to a ‘kart’ and built-in GPS, with which he took an X-ray of the subsoil.
“In this X-ray, using this method, we see round houses and square houses with the ground-penetrating radar; here we can see that, in that area down there, there is probably an oven, a forge,” he explained, pointing to a tablet with the information collected.
For Tiago do Pereiro, this is a “very important discovery,” a finding that previous excavations in the last century had not detected. In his opinion, using this technology instead of excavations allows archaeological sites to be better protected.
The company Era Arqueologia leads “Ativar - Local communities and the origins of the agricultural landscape of Barroso,” partners with the municipalities of Boticas and Montalegre, and receives funding from the La Caixa Foundation.
The project manager, José Carvalho, said that, in addition to “activating the castros,” the project also aims to work on memory and identity.
Until November 2026, researchers and experts will work with communities, schools and local associations. They will collect stories about these sites and the memories of those who live there.
José Carvalho said that the team will create and constantly update a website, where the “Atlas of the Castros of Barroso” will be available. The team will also create new routes between the castros, which could become a new tourist attraction, and will film a documentary.
João Fonte explained that this atlas will work like ‘Google Maps’, where clicking on a point will bring up information about the castros, virtual reconstructions and oral memories.
Then, at a later stage, researchers can carry out archaeological excavations.
"For us, this is a very important project that complements the work we have already been doing," said Nuno Teixeira, from the environmental and cultural association Celtiberus, noting that the initiative highlights the "cultural heritage, history and memory of the people of the region" and that Boticas has enormous potential in terms of its castro heritage, "which we must show".
PLI/ADB // ADB.
Lusa
