Sumas Mountain, also referred to as Canadian Sumas to distinguish it from an identically-named mountain just 10 km (6.2 mi) to the south in U.S. state of Washington across the border, is a mountain in eastern Fraser Lowland, in the Lower Mainland region of the Canadian province of British Columbia. It sits on the south bank of the Fraser River, west of the smaller Chilliwack Mountain across the Vedder River mouth, and serves as a geographic landmark dividing the Fraser Valley into "Upper" and "Lower" sections.