The Fraser Canyon is a stretch of the Fraser River where it descends rapidly through narrow rock gorges in the Coast Mountains enroute from the Interior Plateau of British Columbia to the Fraser Valley. Colloquially, the term "Fraser Canyon" is often used to include the Thompson Canyon from Lytton to Ashcroft, as they form the same highway route which most people are familiar with although it is actually reckoned to begin above Williams Lake, British Columbia at Soda Creek Canyon near the town of the same name.