The Illecillewaet has been of importance since the discovery in 1881 of an approach along the river to what is now known as the Rogers Pass across the Selkirk Mountains. This pass, discovered by a surveyor for the Canadian Pacific Railway named Albert Bowman Rogers, ultimately became the route through the Selkirks of Canada's first transcontinental railway. In 1962 the Trans-Canada Highway was constructed along the Illecillewaet west of Rogers Pass.