Mission Ridge, also known as Mission Mountain, is a ridge in the Bridge River-Lillooet Country of the South-Central Interior of British Columbia, Canada, extending westward from the town of Lillooet along the north side of Seton Lake to Mission Pass, which is immediately above and to the north of the lakeside community of Shalalth. The road over the pass is also known as Mission Mountain, which is short for "Mission Mountain Road". Mission Creek lies on the north side of the pass, and is a tributary of the Bridge River, the lower reaches of which lie on the north side of the ridge, and which was the only road access into the upper Bridge River Country before the construction of a road through the Bridge River Canyon in the mid-1950s opened that region up to road access from the lower Bridge River valley and the town of Lillooet via the community or Moha. Most, or virtually all, of the ridge, is Indian Reserves, notably Slosh 1, under the administration of the Seton Lake Indian Band, and Bridge River 1, which is under the administration of the Bridge River Indian Band. Parts of the ridge's eastern end are in reserves controlled by the Lillooet Indian Band, including its final spires above Lillooet, which were dubbed St. Mary's Mount by the Reverend Lundin Brown in the 1860s, though that name never stuck and is ungazetted.
The name derives from the former Oblate Mission at Shalalth. Originally the ridge, which is about 20 km in length, was referred to as Mission Mountain but as another Mission Mountain was already recorded in British Columbia (on the Tsimpsean Peninsula near Prince Rupert) and the term refers really more to a small mountain range than to any one specific summit, the term Mission Ridge was coined in 1931 for official purposes. The British Columbia Geographic Names Information System places the coordinates of the ridge on Mission Peak, which is the westerly of the ridge's three main summits and is labelled on the provincial basemap as such. The other two summits are conjointly referred to as Mount McLean, with the actually-highest of the pair being officially unnamed because it is invisible from the lake and other viewpoints for the ridge (the highest summit is only visible from the Fountain-Pavilion stretch of BC Highway 99), and from Moha. Mount McLean is named for Donald McLean of the Hudson's Bay Company and a casualty of the Chilcotin War.