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Three Dihedrals Rock Climbing

Climbing Area Map This is our best guess at this area's location.
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Routes in Three Dihedrals

L › R R › L A › Z

	A Cheval T 5.8 5b 16 VI- 15 HVS 4c
	Common Denominator T 5.9+ 5c 17 VI 17 E1 5a
	Curvilinear T 5.10a 6a 18 VI+ 18 E1 5a
	Dihedral One T 5.6 4c 14 V 12 S 4b
	Dihedral Two T 5.8 5b 16 VI- 15 HVS 4c
	Dom Perignon T,S 5.9 5c 17 VI 17 HVS 5a
	Dominator S 5.10c 6b 20 VII 20 E2 5b
	Dominatrix T 5.8 5b 16 VI- 15 HVS 4c
	Pillar T,S 5.6 4c 14 V 12 S 4b

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GPS:	39.99889, -105.41204 Google Map · Climbing Area Map
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Shared By:	Ron Olsen on Mar 29, 2006
Admins:	Leo Paik, John McNamee, Frances Fierst, Monty, Monomaniac, Tyler KC Page Updates (admin only)

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Access Issue: Seasonal Closures 2025 - Bitty Buttress, Blob, Eagle Rock &, Security Risk are closed for raptor nesting Details

2/3/25. Bitty Buttress, Blob, Eagle Rock &, Security Risk are closed for raptor nesting.

FS (3/27/24): Eagle Rock & Security Risk are now open!

2/1/24: W. McCurry: to protect nesting golden eagles, USFS annual area closures in Boulder Canyon beginning 2/1/24 - Blob Rock, Bitty Buttress, Eagle Rock, Security Risk.

From W. McCurry: 2/10/23 Blob, Bitty Buttress, & Security Risk opened. Eagle Rock stayed closed - info: fs.usda.gov/detail/arp/news….

W. McCurry, NFS, Arap./Roo. NF: USFS began annual area closures in BC 2/1/23. The closures were Eagle, Blob, Bitty Buttress, & Security.

Through 7/31/23, the closures protect a long-established golden eagle nesting territory. Happy Hour, Bihedral & Riviera will remain open as long as visitors stay out of the closed areas.

The Boulder Ranger District with BCC monitors nesting progress & informs climbers about giving eagles space to raise young.

Fed. & state laws prohibit disturbing any nesting bird of prey. Visitors help protect wildlife by respecting closures. Signs are posted at key access pts into the closed areas. Closure info: fs.usda.gov/goto/arp/eagles.

K. Armstrong, Public Affairs Specialist, Nat'l Forest Service: as of 6/8/21: BC areas reopen after unsuccessful nesting.

K. Armstrong, NF Ranger 7/29/20:

Following a 5 mo. closure to protect nesting eagles, the Roosevelt NF has reopened Eagle Rock.

“The BC eagles successfully raised 1 strong & healthy eaglet this year,” wildlife biologist Aurelia DeNasha, USDA FS. “2 chicks hatched initially, only 1 survived to fledge, which isn’t uncommon in birds of prey.”

Visits to the nest did not reveal the exact cause of death of the 2nd chick, but climber cooperation with closures are crucial to the eagles.

“Golden eagle pairs are most susceptible to disturbance when choosing a nest. These closures allow the birds to pick the best site for survival without impact of other factors, such as human presence. Once chosen, nest sites stays closed until the eagles fledge in late July,” said DeNasha.

After the eagles’ site selection was made, unused areas opened in Apr.

The annual nesting closures include popular rock climbing spots at Eagle, Blob, Bitty Buttress, & Security.

Effective through 7/31/20, the closures protect a long-established golden eagle nesting territory. Happy Hour, Bihedral & Riviera remain open as long as visitors stay out of the closed areas.

The Boulder Ranger District partners with BCC & AF to monitor nesting progress and to inform climbers about the importance of giving the eagles space to raise their young.

It is against federal & state law to disturb any nesting bird of prey. Only employees, volunteers, & wildlife professionals under an agreement with the FS enter nesting areas for monitoring purposes. This is for the integrity of nest & the safety of the eagles, those conducting surveys, & the public. Visitors help protect wildlife by respecting all closures & leaving immediately if you should accidentally enter one.

For the most current closure information, check signs in the areas, call the Boulder Ranger District office @ 303-541-2500, or visit local climbing websites or fs.usda.gov/recmain/arp/rec….

As of 4/21/20, Blob Rock, East Blob Rock, Bitty Buttress, & Security Risk are open. Eagle Rock stays closed until 7/31/2020 confirmed with Matt Henry, Rec Prog Mgr, FS.

From K. Armstrong, FS Pub Aff, katherine.armstrong@usda.gov, 970-222-7607: 3/20/19, Blob, East Blob, Bitty Buttress, & Security are open. Eagle stays closed to climbing & other activities through 7/31/19.

The Boulder Ranger District partners with BCC & AF to monitor nesting progress & to inform climbers.

See - fs.usda.gov/recmain/arp/rec….

Perennial notice:
Eagle, Blob, Bitty Buttress, & Security will close 2/1 - 7/31 for nesting. Depending on updated information, the closure time can be shortened/lengthened.

Each year, BC raptor nesting area closures are in effect starting 2/1 through 7/31 at Eagle, Security, Blob, & Bitty Buttress. The area is monitored & closures are periodically lifted early (due to no active nest, nest site failure, or early fledging). This monitoring program is a partnership with the FS Boulder Ranger District, BCC, & Audubon Society. Check back periodically during times of closure for updates. More info at fs.usda.gov/recarea/arp/rec…

Description

The Three Dihedrals area lies up and right of Tarot Wall. It has one popular sport route, Dominator (10b). The other routes are not frequently climbed, perhaps because they all require gear. Still, if you brought a rack with you, there are some worthwhile trad adventures to be found here.

This area is somewhat disjointed. The most popular face, containing the routes Dominator, Dom Perignon, and Dominatrix, is right next to the Clipboard Area, and is easy to access.

The other routes (Curvilinear, Pillar, Dihedral One, Common Denominator, Dihedral Two) are down and left of the Dominator area.

L->R:

Below and left of Dominator:

A. Curvilinear, 10-, 1p, 40', gear. L-angling crack in secluded alcove.
B. Pillar, 7, 1p, 50', gear & bolt. RFD up L side of pillar.
C. A Cheval, 8, 100', bolts & gear.
D. Dihedral One, 6, 1p, 100', gear. Ramp to RFD.
E. Common Denominator, 9, 1p, 100', bolts & gear. Crack, arete, face.
F. Dihedral Two, 6 or 7, 1p, 100', gear. Ramp to bushy corner.

Dominator area:

G. Dominatrix, 8 or 10-, 1p, 90', bolt & gear. Corner (8) or cracks (10a) to RFD.
H. Dominator, 10, 1p, 60', bolts. Overhanging hand cracks.
I. Dom Perignon, 9+, 1p, 60', bolts & gear. Hand crack.

Getting There

There are two ways to get to the Dominator area:

1. Climb up the talus field above the Tyrolean Traverse. A dirt path starts at the top of the talus. Follow the path uphill a bit until the trail splits. Take the left branch, toward Tarot Wall. After about 10', a faint trail heads off right, up the hill. Follow this path uphill to a big tree at the base of the Dominator wall.

2. Instead of taking the trail to the left heading toward Tarot Wall, continue up the hill on the right trail branch. You'll eventually reach a steep wall with a scooped-out face; this is the route Strange Science. Go left and climb up some big boulders to a flat area. The Clipboard Area is to the right, and the Dominator wall is just left of that, at a right angle to the Clipboard wall. This is the most common approach.

Dominator wall is rust colored, slightly overhanging and laced with cracks; it's hard to miss.

To get to Curvilinear, Dihedral One, Common Denominator, and Dihedral Two:

Use approach #1. Start hiking up the hill toward the Dominator area. After a short distance, a faint path heads off to the left. Take this to get to these routes. You'll see a low-angle slab; that's the start of Dihedral One, Common Denominator, and Dihderal Two. Go another 50' and uphill a bit to get to Curvilinear.

See the route descriptions for more details.