From Libbiano, we enter the Monterufoli Caselli Regional Nature Reserve, one of the wildest areas of Tuscany due to the extension (about 4,800 hectares) of its almost continuous forest cover.
The Regional Nature Reserve is also of high conservation importance given its numerous species of fauna. Among the species of birds we find is the whitethroat (Sylvia cantillans), the magnanina (Sylvia undata) and the passerine bird. Along the numerous streams that run through the Regional Nature Reserve, in addition to the dipper (Cinclus cinclus), there are spectacled salamanders (Salamandrina perspicillata) and the Apennine frog (Rana italica). The symbolic animal of this area, however, is the "Monterufoli horse", an indigenous horse breed that's currently the subject of conservation and promotion activities.
From Querceto, we reach the Ponteginori train station, after having travelled the Sp 47 to return by train to Cecina and then to Pisa where our ideal ring ends.