Entombed by ice, lost souls and legendary allure, the Cascades’ greatest peak has defined the Pacific Northwest’s history and horizon for centuries. Protected by John Muir, America’s greatest conservationist, Rainier’s tale has risen from volcanic marvel to yesteryear’s winter wars and now to modern-day tests of ski mountaineering mettle. In a twist of past and present, we explore one of the continent’s most iconic mountainscapes. By Colin Wiseman