Valle dell'Ardo deeply furrows the western slope of Schiara group, venturing - often confined in wet and gloomy ravines - as far as the gates of Belluno. Its head is closed by the imposing dolomitic Schiara group (2,565m), the highest peak of the Park. The frequent stretches of ravine witness the important role played by the stream Ardo in the morphological evolution of the valley. Two spectacular ravines are evidences of as many detours of the course of the stream: Bus del Busón and the ravine of Pont de la Mortìs.
The vegetation is rich in coppice woodlands, above all beech tree woods, but there are also considerable stretches of woods dominated by Hornbeam in the more fertile areas and by Hop Hornbeam in the driest ones, and locally there is a reasonable presence of Silver Fir (Val Rui Fret). Interesting, in the shadowy ravines, the abundant presence of yew, a rather rare arboreal species. At higher altitudes and in the rocky areas, the Stone Pine dominates. Among the most interesting floristic species we can observe in Valle dell'Ardo we quote three endemic species of the Dolomites: Primula tyrolensis, Rhizobotrya alpina, and Campanula morettiana. The valley houses a rich alpine wildlife; along the stream you can frequently observe the Dipper while, also at low altitudes, you can easily sight the chamois.