The valley takes its name from the Brunone stream that flows through it, making a perfect bank for a richly wooded landscape, which is interspersed with small grasslands with paths leading to rustic isolated cottages.
The importance of the place is due to the bucolic landscape and the black mudstone outcrops discovered in 1973: rocks that preserve a rich fossil fauna dating back to the Upper Triassic, or more than 200 million years ago!
Among the finds are reptiles, fish, crustaceans and insects.
The most spectacular, however, is represented by a dragonfly known as Italophlebia gervasuttii, which magically preserves intact the network drawn by the ribs on its wings.
To protect this treasure-rich area, since 2001, on the initiative of the Bergamo Museum of Natural Sciences, the Brunone Valley site has been recognized as a Natural Monument.
The protected area, located near Ponte Giurino, encompasses the middle and lower reaches of the Brunone Stream, a tributary of the Imagna Stream, and is located in mixed deciduous forests.
But there is another peculiarity that makes this valley unique: the sulfur springs.
The process that leads to the formation of these waters is complex and starts several kilometers away, from the waters that flow from the argillites of a village near the lake: Riva di Solto, in which sulfides are present.
Their healing properties are mentioned as early as 1876 by nineteenth-century scientist Antonio Stoppani in his work “Il Bel Paese.”