This is elegant mixed couloir was first climbed by P Decorps and G Perroux in December 1979. It lies directly to the right of the North face
, is slightly steeper (average 60°) and less crowded than the popular north face. The route is more regularly in condition than the Gabarrou Pointi route further west.
The walk-in to la Tour Ronde from the Col du Midi
From the Aiguille du Midi
station or the Cosmiques hut
head south-east across the Col du Midi. Descend the Glacier du Geant skirting the couloirs of Mont Blanc du Tacul
to the right. Continue south past Tacul navigating through crevasses to reach la Tour Ronde
in approximately one hour from the Midi Station / Cosmeques hut. The North Couloir is directly to the right of the prominent snow slopes of the north face.
The starting point will depend upon how lean the conditions are. Towards the end of summer it may be easier to start the route via a snow funnel to the right of the regular starting point in order to avoid lean blue ice. Having crossed the bergshrund bare left to regain the couloir. This alternative start is not straight-forward as there is a tricky mixed step before the bolted rock that will prove the crux move of the day. Climb the couloir for around five pitches navigating through sections of semi-loose rock and good ice. When I climbed the route late summer there was particularly good ice around the middle pitches. Steepness of the couloir varies between 55 and 70°. Belays lower down are particular precarious due to much of the rocks being loose. Towards the top of the couloir there are two possible finishes. Either bare left to join the north couloir, cross to its left side then descend the South-East Ridge
or stay in the couloir for its entirety, descend to the Gervasutti Couloir
and down-climb it (45 - 50°). The Gervasutti Couloir
can easily be abseiled in to via in-situ pegs and slings from the ridge however its bergshrund can be difficult to cross in the late season. Those wishing to summit la Tour Ronde
should opt for the former finish line.
|Decorps-Perroux Couloir with Variations |
|Topo of routes
Nuts and slings are most useful for this route
Also bring a selection of hexes, pegs and cams