La Tour Percée is a wonderful double arch located above Marcieu Pass on "Les Petites Roches" cliffs near L'Aup du Seuil in the Regional Natural Park of La Chartreuse. The largest opening has 32 meters span. The hiking and climbing route to the arch was pioneered by Pascal Sombardier (silhouetted on the opening) in may 2005. Can you imagine these arches were totally unknow until now since they are located only 25km (17 mile) from Grenoble, a city about 400 000 peoples ? It is amazing but the answer is yes! From this time the arch attracted attention to general public.