New Pull-through Routes in the Dent de Crolles System

[langcliffe]

For anyone venturing to Chartreuse this year and wanting to try something new, Spéléo Secours Isère have produced topos for two newly equipped pull-through routes in the Dent de Crolles system. Both of them start in the Gouffre Bob Vouay, situated just 200 m from and 47 m below the summit of the hill.

The first route goes through to Grotte Chevalier, 322 metres lower (although the greatest depth reached is about -460 metres). The second route exits through Trou du Glaz, some 325 metres lower. The latter can be combined with one of the two equipped routes to the resurgence at the Grotte du Guiers Mort, to make it a 681 metre-deep pull-through. I understand that neither of the two routes are easy, involving lots of hairy and arduous meander work.

Loose translations (caveat emptor!) of the route guides have been provided on my Réseau de la Dent de Crolles website, where various relevant surveys may also be found. The following cross-section shews the two routes. Magenta(?) is common to both; red leads to Grotte Chevalier; and blue leads to Trou du Glaz.

 

[langcliffe]

I have come across a web article about the bolting of these two traverses.

 

[meanderthal]

Hi Langcliffe,

Thanks for your efforts translating the descriptions. 3 of us did the pull through from Bob Vouay to Guiers Mort over the weekend. Excellent trip and very little confusion with the description.

Just for note, there were a few additional short pitches in the meanders that weren't in the description- although these were all rigged. A couple of the pitches we rigged did come a up a bit longer than in the description, but all were easily possible with the ropes we had (40m, 35m, 30m and 10m of additional cord).

 

[langcliffe]

Well done! I'll add a couple of "editor notes" to the description following your feedback. Would you say that 3 * 35m ropes were right for the first half?

I would love to see a trip report if you do one.

 

[Fjell]

Is this harder (smaller) than P40?

 

[meanderthal]

I haven't done the P40. But a couple of friends did over the weekend. It seems like the meanders in the P40 are tighter, but those in the Bob Vouay are never desperate, but longer (much longer!). It took them 4 hours to do P40 to Trou de Glaz and us around 7 hours from Bob Vouay to the end of the 'Grande Meandre' / top of the P36. I'd say the two teams would usually cave at a fairly similar pace. Overall, it seems to be a harder trip, though with no show stopping meanders.

I *think* the pitches we found to be longer than expected were:

• Ressaut Hervé which is rigged as 1 drop of 25m not 2 drops of 3m & 21m.
• the 2nd pitch of the Puits du Fer à Cheval was more like 26m+

So nothing dramatic, but rope faff slowed us down a bit.

At the bottom of the Puits du Carrefore there were two meanders, the Meander Pecheur Double is the left one. This meander was mostly traversing at mid height & started to get a bit airy before we reached the hand line and made us question ourselves.

3x 35m ropes would get you down the Bob Vouay. We took a 40m to get down the P36 and continue into the Guiers Mort trip.