Col du Coq Road Closure
Following a landslide on the night of 10 December 2017 which covered the Route du col du Coq with 3,000 m³ of debris, and caused 50 metres of the road to be invaded by the Ruisseau de l’Orme, the Col du Coq is currently inaccessible from the St Pierre de Chartreuse side, although it remains accessible from the east. The good news is that the task of rebuilding the road began on June 10th 2019, but it is unlikely to be reopened before the late summer. See the July 2019 municipal newsletter for the latest official information.
The closure obviously complicates logistics for some of the through trips. Typically a through-trip from a top entrance to the Grotte du Guiers Mort involves leaving cars at both Col du Coq and Perquelin. That is now impractical without a very long drive round via the Col de Porte and the Grésivaudan valley to pick up the first car. The only alternative is to walk back from the Grotte du Guiers Mort via Trou du Glaz and the Col des Ayes, which is a pain in caving gear.
For people staying on the St. Pierre de Chartreuse side of the col wishing to do anything on the plateau, it will be necessary to walk up from Perquelin - again, a pain carrying caving gear.
If wishing to do through trips to Trou du Glaz from P40 or Gouffre de la Pulpite Irréversible, or from Trou du Glaz to Grotte Annette Bouchacourt or Grotte Chevalier, it is best to stay on the east side of the col - there is camping available at Saint Hilaire du Touvet. Anyone wishing to do a through trip to Grotte du Guiers Mort should be prepared for a long walk back.