Until 1980, the municipal territory of Piazzolo, a settlement in the Brembo di Mezzoldo valley, had an additional portion beyond the ridge of Corna Rossa, forming a spur between the territories of Piazza Brembana and Olmo al Brembo. This cross marks the boundary point between Olmo al Brembo and Piazzolo..
Located at a height of 724 metres, straddling path 105B, this is a wide arch in the rock wall. A rustic stone building stands next to it.