In the last two million years on our planet there have been alternating temperate periods and periods of extreme cold. The last of these (Würmian) periods began 75,000 years ago and culminated 35,000 years ago when in Western Eurasia homo sapiens sapiens was differentiating from Homo Neanderthalensis. 10,000 years ago the glaciers progressively retreated in the most internal and highest areas whereas up until that point the Alps and Prealps had remained almost completely buried. Among the most evident geomorphological effects of the erosive action of the ice were (…) the so-called U-shaped valleys, created by glacial excavation.
These include the upper Valsugana, where the main Adige and Piave glaciers merged and an ice sheet stretched down to Valstagna. Its meltwaters formed what we could in some way identify with as the Brenta river.