Mount Formidable is a

mountain A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited Summit (topography), summit area, and ...

in the

North Cascades The North Cascades are a section of the Cascade Range of western North America. They span the border between the Canadian province of British Columbia and the U.S. state of Washington and are officially named in the U.S. and Canada as the Cascad ...

Skagit County Skagit County is a county in the U.S. state of Washington. As of the 2020 census, the population was 129,523. The county seat and largest city is Mount Vernon. The county was formed in 1883 from Whatcom County and is named for the Skagit Ind ...

, in

Washington state Washington (), officially the State of Washington, is a state in the Pacific Northwest region of the Western United States. Named for George Washington—the first U.S. president—the state was formed from the western part of the Washington ...

. Its first ascent was undertaken by members of the original Ptarmigan Traverse, and the peak is a popular climb for parties on the traverse. It was named by early mountaineer Herman Ulrichs in 1935 because of the rugged appearance of its north face. The peak is usually accessed from

Cascade Pass Cascade Pass (formerly also known as Skagit Pass Dome Peak Dome Peak is a high, massive, glaciated mountain in the Glacier Peak Wilderness of Washington's North Cascades. The remote location of Dome Peak, combined with its height, make it a less common destination for Cascade Range mountaineers. Dome P ...

, and about a mile west of

Spider Mountain Spider Mountain is an mountain summit located in the Glacier Peak Wilderness in western Chelan County of Washington state. It is part of the North Cascades, which is a subset of the Cascade Range. Meltwater from the Spider Glacier on the s ...

. It is within the

Marine west coast An oceanic climate, also known as a marine climate, is the humid temperate climate sub-type in Köppen classification ''Cfb'', typical of west coasts in higher middle latitudes of continents, generally featuring cool summers and mild winters ( ...

climatic zone, and experiences heavy snowfall as a result. The surrounding area is part of the

Pacific temperate rainforests The Pacific temperate rainforests of western North America is the largest temperate rain forest region on the planet as defined by the World Wildlife Fund (other definitions exist). The Pacific temperate rainforests lie along the western side of ...

ecoregion, and lower elevations are densely vegetated. The

Middle Cascade Glacier Middle Cascade Glacier is in Wenatchee National Forest in the U.S. state of Washington and is to the north of Spider Mountain and east of Mount Formidable. Middle Cascade Glacier has a significant icefall that is thinning and may eventually separat ...

, which drains into the

Skagit River The Skagit River ( ) is a river in southwestern British Columbia in Canada and northwestern Washington in the United States, approximately 150 mi (240 km) long. The river and its tributaries drain an area of 1.7 million acres (690,000& ...

via the Cascade River, is on the north side of the mountain.

Geology

The North Cascades are composed of terranes, or scattered, unrelated rock groups of various ages. More specifically, the immediate area surrounding Mount Formidable (i.e., within ten miles), is mainly composed of

granitic A granitoid is a generic term for a diverse category of coarse-grained igneous rocks that consist predominantly of quartz, plagioclase, and alkali feldspar. Granitoids range from plagioclase-rich tonalites to alkali-rich syenites and from quart ...

rocks that are Mesozoic in age, and

schist Schist ( ) is a medium-grained metamorphic rock showing pronounced schistosity. This means that the rock is composed of mineral grains easily seen with a low-power hand lens, oriented in such a way that the rock is easily split into thin flakes o ...

that dates from the late

paleozoic The Paleozoic (or Palaeozoic) Era is the earliest of three geologic eras of the Phanerozoic Eon. The name ''Paleozoic'' ( ;) was coined by the British geologist Adam Sedgwick in 1838 by combining the Greek words ''palaiós'' (, "old") and ' ...

. Mount Formidable itself is likely composed of originally igneous rocks that formed in the

Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period ...

and were metamorphorphized in the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the ...

. (cited in Beckey 2003)

Climbing

Mount Formidable is usually accessed via the Ptarmigan Traverse, which begins at Cascade Pass. Climbers ascend from Cascade Pass to Cache Col via the

Cache Col Glacier Cache Col Glacier is in North Cascades National Park in the U.S. state of Washington, on the east slope of Mix-up Peak. Cache Col Glacier retreated nearly between 1950 and 2005. Cache Col Glacier is northwest of Yawning Glacier. See also *List ...

, then traverse toward Kool-Aid Lake, a small, alpine lake that drains into the Middle Fork of the Cascade River. Climbers then typically traverse south towards the

via the Red Ledges, then around the south side of the mountain to the summit. There are, however, alternative routes, most of which involve ascending from the Middle Cascade Glacier.

References

External links

* *
Mount Formidable
on Summitpost.org
Mount Formidable
on Flickr {{Authority control North Cascades of Washington (state) Formidable Formidable Formidable