In the mountainous area between Cortaccio, Rescerasca, and Penseverone, located directly along the Swiss-Italian border, there was a significant influx of people during the period of 1943-1945. This region became a refuge for those fleeing the persecutions of the Nazi fascists, for former Allied prisoners, and even for various smugglers. The influx of individuals into this area had mainly two origins: one from the slope of Alpe di Frignago (elevation of 1157 meters) and the other directly from Gridone/Ghiridone/Mount Limidario (elevation of 2186 meters), passing through Alpe Arolgia (elevation of 1729 meters).
In the cantonal and federal archive documents, there are at least a hundred interrogation files concerning individuals detained by the Swiss Border Guards within this zone. The majority consisted of persecuted people, but there were also cases of fascists who had not joined the Italian Social Republic (RSI). There are also documented cases where Jews and Italian civilians were rejected. The peak of this human flow occurred during the winter of 1943-1944, gradually decreasing throughout 1944. This change is mainly attributable to the increase in German and fascist military operations along the Swiss border.
During the final phases of the fighting for the partisan "Free Zone" in Ossola, there was a brief increase in the influx of refugees. Smugglers crossed the border in the same region but preferred significantly higher-altitude routes, making it difficult, if not impossible, for the respective Swiss-Italian border guards to detect them.
There were also human losses in the border area: in January 1945, just above Cortaccio, near Alpe Arolgia, a group of nine former prisoners was engulfed by an avalanche and lost their lives. However, border crossings in this area also occurred in the opposite direction, towards Italy. Numerous commanders and partisans, after receiving assistance or having been replenished on Swiss territory, returned to Italy through this sector.