The Tour Percée double arch, also named the Tour Isabelle arch, is a double

natural arch A natural arch, natural bridge, or (less commonly) rock arch is a natural landform where an arch has formed with an opening underneath. Natural arches commonly form where inland cliffs, Cliffed coast, coastal cliffs, Fin (geology), fins or Stack ...

, located in the Parc Naturel Régional de la Chartreuse,

Chartreuse Mountains The Chartreuse Mountains ( ) are a mountain range in southeastern France, stretching from the city of Grenoble in the south to the Lac du Bourget in the north. They are part of the French Prealps, which continue as the Bauges to the north and ...

, France. Its span is , which makes it the widest natural arch in the

Alps The Alps () are some of the highest and most extensive mountain ranges in Europe, stretching approximately across eight Alpine countries (from west to east): Monaco, France, Switzerland, Italy, Liechtenstein, Germany, Austria and Slovenia. ...

. It remained unknown for probably everybody, until its discovery in May 2005, when Pascal Sombardier, who was trekking to write his book ''Chartreuse inédite : Itinéraires insolites'', dealing with lost places of the range, discovered it fortuitously. Its pictures illustrated the front cover of his book, published in 2006 : this double arch became then the symbol of the hidden treasures of the Chartreuse Mountains. Located in a very remote area, with a difficult and dangerous access, very few

guide book A guide book or travel guide is "a book of information about a place designed for the use of visitors or tourists". It will usually include information about sights, accommodation, restaurants, transportation, and activities. Maps of varying det ...

s, even the most recent ones, mention its existence. File:Dawn on Tour Isabelle (South face).jpg, Dawn on Tour Percée (South face) File:Tour Isabelle in the Spring time.jpg, Tour Percée in the Spring time File:Tour Isabelle neighboring skulls.jpg, Tour Isabelle neighboring skulls File:Tour_Isabelle_right_after_dawn.jpg, Tour Percée right after dawn File:Tour Isabelle with person over main arch to give scale.jpg, Tour Isabelle with person sitting above the main arch to give scale File:Tour Isabelle with person under main arch to give scale.jpg, Tour Isabelle with person standing under main arch to give scale File:Winter sunrise on Tour Isabelle.jpg, Tour Isabelle in the Winter time File:Double-arch.jpg, The double arch

References

Natural arches of France Geography of Isère Alps {{Isère-geo-stub