Other highways were built during the 1950s and 1960s, resulting the decline and disappearance of the riverboats that had provided the main means of transportation until the 1960s. In the 1950s, the White Pass & Yukon Route pioneered the use of intermodal containerized shipping. Mining activity also revived, including copper mining in Whitehorse, silver and lead in Keno and Elsa, asbestos in Clinton Creek. The world's largest open-pit zinc and lead mine was opened in Faro in the early 1970s. Gold mining came back to the Klondike and other areas with the large rise in gold prices in the late 1970s.