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Routes in River Boulder

Irregular Arete V1+ 5
Regular Route V2- 5+
Thunderslap V4 6B
Type: Boulder, 10 ft
FA: unknown
Page Views: 90 total · 2/month
Shared By: Tane Owens on May 26, 2013
Admins: Andrew Gram, Peter Gram, Greg Parker, Andy Busse, Mike Madsen, Mark Rafferty

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I believe this route is technically a harder variation to the Irregular Arete. Start low on the upstream end of the River Boulder on the two jugs on either side of the bulge. Get low and difficult to see feet, or a heel/toe hook around the right edge. Manage your way up the bulge with a couple powerful throws and slaps up the arete feature to your right.

  • This problem is an eliminate and does not use the face to the left of the bulge and stays on the bulge itself the entire time. If you use the face then you climbed the original problem, Irregular Arete V1.


To get to the river boulder, take the first left in the park, park right away. Hike up the street until you get to a trail on the right. Walk down the stairs and follow the trail down river until you see an obvious boulder on the right about 100 feet down the trail.
The problem is on the upriver (east?) side of the River Boulder and follows the bulge straight up.


The low crux can be protected easily with one pad but it would have been nice to have another and a spotter for the top out.


Tane Owens
Denver, CO
Tane Owens   Denver, CO
I was a bit thrown off by the useful kneebars when I read the description to Irregular Arete, so I assumed that the face to the left was used for that problem. If not, then I'm curious as to where to place a kneebar. All-in-all I was a little confused about the Irregular Arete description and this seemed like the most logical way to climb the arete without the use of the face to the left. I could be quite wrong though.

This is actually the only reason I took the vid with my phone so I could maybe clear up a little confusion. Up to you Jon. Does the Irregular Arete use the face to the left? Either way, I thought they were both super fun variations. Jun 2, 2013
Jon Marek
Sioux Falls, SD
Jon Marek   Sioux Falls, SD
Mike is right. This is the irregular arete, exact same holds I promise there is an easier way to do this.

Edit to add: the new description makes it more clear that this route is an eliminate problem. (irregular arete, inset left wall is off.) May 29, 2013
Mike Madsen
Rapid City
Mike Madsen   Rapid City  
Great Video. Yes, If I remember right I watched Jon do the Irregular Route and this is pretty much identical except the slaps. Looks like a good fun problem! May 29, 2013
Tane Owens
Denver, CO
Tane Owens   Denver, CO May 26, 2013

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