The Athabasca oil sands were first described by fur trader and explorer Alexander MacKenzie in 1801. However, serious mining of the resource on the scale shown in this lantern slide did not begin until a century later when the bitumen and sand mixture was used to pave some Edmonton streets. The International Bitumen Company and Abasand Oils Limited only started producing asphalt from the sands in the early-1930s. Full-scale oil extraction would have to wait until a process was developed after the Second World War.