| Williams Peak | |
| Elevation M: | 2123 |
| Elevation Ref: | [1] |
| Prominence M: | 793 |
| Range: | Skagit Range North Cascades |
| Parent Peak: | Foley Peak (2293 m) |
| Listing: | Mountains of British Columbia |
| Location: | British Columbia, Canada |
| District: | Yale Division Yale Land District |
| Coordinates: | 49.1294°N -121.5053°W |
| Map: | Canada British Columbia#Canada |
| Label Position: | top |
| Type: | Intrusive |
| Volcanic Arc/Belt: | Pemberton Volcanic Belt |
| First Ascent: | 1908 by James J. McArthur and E.T. de Coeli |
| Easiest Route: | Scrambling |
Williams Peak is a prominent 2123abbr=offNaNabbr=off mountain summit located in the Chilliwack River valley of the Cascade Mountains in southwestern British Columbia, Canada. It is situated 140NaN0 north of the Canada–United States border, 60NaN0 northwest of Chilliwack Lake, and 6.70NaN0 southeast of Foley Peak, which is its nearest higher peak. Williams Peak is the highest point of the South Hope Mountains, which is a subset of the Skagit Range.[2] Precipitation runoff from the peak drains into tributaries of the Chilliwack River. The mountain's name was officially adopted April 7, 1955, by the Geographical Names Board of Canada.[3] Williams Peak was first climbed July 1908 by James J. McArthur and E.T. de Coeli via the southwest ridge.[1]
Williams Peak is related to the Chilliwack batholith, which intruded the region 26 to 29 million years ago after the major orogenic episodes in the region. This is part of the Pemberton Volcanic Belt, an eroded volcanic belt that formed as a result of subduction of the Farallon Plate starting 29 million years ago.[4] [5] [6]
During the Pleistocene period dating back over two million years ago, glaciation advancing and retreating repeatedly scoured the landscape leaving deposits of rock debris.[7] The U-shaped cross section of the river valleys is a result of recent glaciation. Uplift and faulting in combination with glaciation have been the dominant processes which have created the tall peaks and deep valleys of the North Cascades area.
The North Cascades features some of the most rugged topography in the Cascade Range with craggy peaks and ridges, deep glacial valleys, and granite spires. Geological events occurring many years ago created the diverse topography and drastic elevation changes over the Cascade Range leading to various climate differences which lead to vegetation variety defining the ecoregions in this area.
Based on the Köppen climate classification, Williams Peak is located in the marine west coast climate zone of western North America.[8] Most weather fronts originate in the Pacific Ocean, and travel east toward the Cascade Range where they are forced upward by the range (Orographic lift), causing them to drop their moisture in the form of rain or snowfall. As a result, the Cascade Mountains experience high precipitation, especially during the winter months in the form of snowfall. Temperatures can drop below −20 °C with wind chill factors below −30 °C. The months July through September offer the most favorable weather for climbing Williams Peak.
Established rock climbing routes on Williams Peak:[1]