Alagna and Riva have always been closely connected but rival communities, both for their geographical continuity and the historical events they have in common. Today as yesterday, they need each other, each maintaining their own identity and at times competing for supremacy which has alternated between them, throughout the centuries, but nevertheless highlighted its mutual destiny.
Formerly they were a single community known as Pietre Gemelle, a name that implies their double identity from the beginning and was symbolized by the two impressive twin rocks still visible today in the garden of the residence with the same name.
In medieval times, Pietre Gemelle had two separate communities: Riva, the oldest settlement, occupied the more level areas farther to the south and had a typical Valsesian character; Alagna which settled on the northern meadows, was of German descent and spoke the Walser language.
To identify the area in question, two place names existed that were expressed in their respective languages: the Valsesian Pietre Gemelle (lt. Petriszumellis) and the Walser Pressmell, but only one town council and parish existed.
Today become a solo municipality invest in high quality tourist development, concentrating on sport, history and nature which has made ancient Pietre Gemelle the Door to Mont Rosa in summer and a Free Ride Paradise in winter, a feather in the cap of the variegated context of XXI century Valsesia.