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YDS: 5.10+ French: 6b+ Ewbanks: 21 UIAA: VII+ ZA: 20 British: E3 5b

Type:  Trad, 1 pitch, 60'
Original:  YDS: 5.10+ French: 6b+ Ewbanks: 21 UIAA: VII+ ZA: 20 British: E3 5b [details]
Page Views: 1,084
Submitted By: blakeherrington on Dec 10, 2010

You & This Route  |  Other Opinions (8)
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Matt lounging on "Undertow".

Road & nearby private property MORE INFO >>>


Smack dab in the middle of the Quarry Wall, and very obvious from the hike in, is a large flake that resembles the profile of a person looking to the South. Undertow follows this flake / right-facing corner to a bolted anchor near the top of the wall. The climb is a good mix of smearing, laybacking, jamming, and powerful underclings.

There's an optional two-bolt start that joins the route after the initial undercling, but the complete flake, starting at the base, makes for a more continuous climb.


This is in the middle of the Quarry Wall.


Single set of cams to 4" or 5", your big piece can be placed early on.

Photos of Undertow Slideshow Add Photo
Rock Climbing Photo: For the direct start, there are two bolts, the top...
For the direct start, there are two bolts, the top...
Rock Climbing Photo: View of Quarry Wall on the approach.  "Undert...
View of Quarry Wall on the approach. "Undert...

Comments on Undertow Add Comment
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By Lisa Montgomery
From: Golden, CO
Oct 1, 2013
rating: 5.11- 6c 22 VIII+ 22 E3 5c

This is a very worthy climb, especially once you've climbed the classics at Thunder. We did the bolted start, which is a nice option if you didn't bring the larger gear. I thought the crux of the route was placing the gear as you work left to right across the undercling flake. You get good gear, it's just a bit strenuous and awkward to place, so no reason not to get on it. Gear recommendation: 2 x green Alien size to #1, 1 x #2.
By Kent Pease
From: Littleton, Colorado
Sep 6, 2014

A great route and one of the best at Thunder Ridge! It requires a variety of skills, first for the climbing techniques and also for gear placements which are sometimes “under the gun” and/or difficult to see. Bring your big gear, and do the wide flake start, otherwise you’ll cheat yourself out of some great moves. I used a 9” Valley Giant and a #5 Camalot (old sizing/ = new #6) for the start and was glad to have both. You could do it more boldly with only one biggie though. A #4 or new #5 Camalot are not adequate. In my opinion, a step or two up in difficulty from other climbs at Thunder Ridge within the grade range when considering the technical level, strenuous power moves, and overall continuity of the climbing.

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