It is a wide a marshy basin of glacial origin, which is situated on the Altipiano di S. Colomba, encircled by the scotch fir woods (Molulio-Pinetum) with a pool at the center, and the combination of Nymphaeetum albae and Cladietum marisci, and wide moist meadows (Schoenetum ferruginei and Junco-Molinietum).