Col du Coq Road Closure
Following a landslide on the night of 10 December 2017 which caused 50 metres of the Route du Col 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 authorities are committed to rebuilding the road, but the project is still at the evaluation stage and, according to the locals, the road is unlikely to be re-opened before 2020. See the June 2018 and July 2018 municipal newsletters for the latest 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.