Lake Valletta Alta is located in a moderately frequented area of the Park. It is a small basin of elongated and roughly rhomboid shape at 2215 m below the imposing tonalite S. Valentino Ridge. It is being filled up by the deposits of the tributary.
In the area of the inflow it is possible to observe the progressive process of burial that is affecting the pond. The inflow enters the lake today, occupying about a third of it. In a few hundred years, at the end of this process a small peat bog will evolve, which will stand out with its cotton grasses, willows, mosses and carnivorous plants, also present today with the species Pinguicola leptoceras. The pond is surrounded by boulders of tonalite in which the biotite mineral is present. You can see that the flakes of biotite flattened and rounded by transport in water are exploited by the Trichoptera Limnefilidi insects present in the lake for the construction of their protective cases.