Noah's Ark
9 boulder problems · Biotite gneiss · 9,248 ft
What's here
V1 to V6, with no single grade dominating.
Counted from the 9 climbs here that carry a grade. Shown only where there are at least 5 of them — below that the shape is noise.
How well located
Position on wall known 9
No route here has its own point yet. The map pin is the crag. At the wall? Survey it: 30 seconds per route.
The order of the climbs along this wall is known from the open catalogue, so a few surveys go a long way: standing at The Wormy, Slab-a-dab (2 climbs, about 60 seconds) would place up to 7 more climbs between them. Survey the wall →
“Up to” because the estimate between two surveyed routes is only used when they turn out to be close enough together on the ground.
Rock, from the geologic map
Biotite gneiss. Paleoproterozoic, about 2,500 to 1,600 million years old.
Gray, medium-grained, equigranular, well-foliated gneiss typically containing approximately 25–50 percent quartz, 20–30 percent plagioclase (approximately An30), 0–30 percent microcline, 10–15 percent biotite, 0–15 percent muscovite, 0–10 percent sillimanite, 0–5 percent hornblende, 1–2 percent opaque minerals, and a trace zircon. Most outcrops contain 5–20 percent granitic layers (leucosomes). Sillimanite, where abundant, occurs in fibrous, elongate, light-colored aggregates or clots as wide as about 1 cm. Migmatitic biotite gneiss in Clear Creek gave preliminary U-Pb zircon date on nonmelt phase of 1,773±18 Ma; near Pine, just south of map area, similar rock gave U-Pb zircon date of 1,780±9 Ma (W.R. Premo, unpub. data, 2005)
This is the map unit under this crag's map point, read from the 1:100,000 sheet (Kellogg and others, 2008, USGS Geologic Investigations Series 3000). The point can be a few hundred metres from the rock, a cliff often stands on the line between two units, and at that scale a line on the map is about 100 m wide on the ground, so the wall itself may be the neighbouring unit. Every crag on this unit: Biotite gneiss. Geology data: Macrostrat (CC BY 4.0), serving USGS and Colorado Geological Survey maps.
On the map since 1905
The USGS has mapped this ground since 1905. 29 historical sheets cover this crag's map point; the oldest is below.
USGS Historical Topographic Map Collection · Public domain · the record · placed by its coordinates
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Hidden as soon as you tell us, everywhere it appears, before anyone reviews it.
Public domain, U.S. Geological Survey. The sheet shows the ground as the survey found it then, which is why a trail or road you know may be missing. Every sheet over this point, 1905 to 1983: USGS topoView.
Photographs near this crag
Taken within 1.5 km of this crag's map point and published under a licence that lets us show them, from Wikimedia Commons. The coordinates say where the camera was, not what it was pointed at, so some of these will be the creek or the trail rather than the rock.
Wikimedia Commons · CC BY · the record · placed by its coordinates
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Hidden as soon as you tell us, everywhere it appears, before anyone reviews it.
Wikimedia Commons · CC BY-SA · the record · placed by its coordinates
Report this item
Hidden as soon as you tell us, everywhere it appears, before anyone reviews it.
Routes
Photos from climbers
No photos here yet. If you're at the crag, yours would be the first.
Taken at the crag by climbers and published as they sent them. Each one's own location had to be within 0.5 km of this crag before we accepted it. See something that shouldn't be here? Use Report this photo under it and it's hidden at once. Anything else, write to us.
Conditions reported
Nothing reported recently.
Report what you see
Reports are dated and fade on their own: wet rock after 3 days, a bad bolt after a year. No names, no text.
Access & safety
The map point for this crag is on land managed by Roosevelt National Forest (federal). It lies inside national forest.
The boundary is close. Land managed by Denver Water Board, Private or Boulder County, CO comes within 250 m of this point, and the point is not the rock — the wall itself may be on the other side of the line. Check which before you rely on either one's rules.
Land manager from USGS PAD-US (public domain), read 2026-09-29. It is the manager of the crag's map point, which can be a long way from the wall. What you may do on the rock is the manager's to say, not ours.
Rules for all Arapaho and Roosevelt National Forests land
- Fees
- No entrance fee for the forest. Some locations require a reservation, pass, permit or day-use fee.
- Overnight
- Camping more than 14 days in a 30-day period, or more than 30 days in a 365-day period, is prohibited across the forests and the Pawnee National Grassland. Dispersed camping is within 300 feet of most Forest Service roads, on National Forest land; the MVUM shows which.
Read on Arapaho and Roosevelt National Forests's own pages, checked 2026-09-29 by John Crawford. What they require, in full, or their own climbing page. These apply to the manager's whole holding; anything specific to this crag is above.
Nearby, from OpenStreetMap
- Toilets
- 1,860 m away (map)
- Mapped parking
- 383 m away (map)
- Campsite
- East Portal Distributed Camping Area, 928 m away (map)
Distances are a straight line from this crag's map point, which can itself be hundreds of metres off; a road may be much longer. Mapped by OpenStreetMap contributors (ODbL), so a toilet missing here may simply be unmapped. Parking here is what OSM has drawn nearby, not a guidebook's directions.
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