Plaine de l'arbre

Today we went on a beautiful 13miles walk, with only 500m ascent on the Haut Plateau du Vercors above the ski tows of Station du Col du Rousset. We walked over alpine meadows, up to the self explanatory Plaine de l'Arbre, where we had a leisurely picnic at 1800m (extra). We also saw a roman quarry at about 1700m - why and how did they got stone out, I have no idea! 
In the evening, my sister and my mother joined us and we took them for a meal out.