The ancient term is arcem Arnulphi, a Lombardic place name consisting of an appellative followed by a Germanic personal name.

The castle of Roccanolfi was built along the crest of a hill on a steep slope to guard the access routes to the Valle Oblita: from Preci, from Corone and further south from Abeto.

A few traces of the ancient castle, such as the highest tower, the compact buildings and the traces of a gate in the higher part, can still be seen. It was also accessed by the roads coming from within the Valle Oblita and its rural settlements.

The village still maintains its original characteristics and shows no sign of any tampering or recent transformations, but it is a seriously bad condition. At the centre of the settlement stands a lordly building on a very steep slope; the parish church, on the other hand, lies lower down at the edge of the settlement.

The tower (and the access path) that dominates Roccanolfi is called “della Regina” (the Queen’s). According to oral tradition, queen Nolfa or Arnolfa frustrated by married life, swore to retire among the mountains in a castle that no-one (not even her husband) has ever found.