corse view on refuge ortu di piobbu first part of gr 20 famous trek with green birch tree sharp mountain peak and blue sky

2017 and birch birche bivaco blue bushes corse corsica countryside destinations famous first forest france gr20 grass green haut height high hike june landscape mountain nature ortu outdoors panorama part peak pine piobbu refuge scenic sharp sky spruce stones summit top tourism tracking travelling tree trek trekking view walks wood