Willis Wall, Volcanic cliff at Mount Rainier, Pierce County, United States

Willis Wall is a volcanic cliff on the north face of Mount Rainier in Pierce County, Washington, rising more than 3,500 feet above the Carbon Glacier below. The face is made up of layers of rock and compacted volcanic material, topped by a thick crown of ice that overhangs the upper section of the wall.

The wall honours geological engineer Bailey Willis, who helped build the first trail to the Carbon Glacier in 1881 and later pushed for the bill creating Mount Rainier National Park in 1899. Charles Bell made the first ascent of the West Rib in June 1961, a solo climb doubted until Jim Wickwire and Dee Molenaar verified it. Wickwire and Alex Bertulis made the first winter ascent in 1970.

The Willis Wall is known in climbing circles as one of the most demanding ice routes in North America. Completing a route on this face carries real weight among alpinists and is seen as a serious achievement.

This wall is only for climbers with solid ice climbing experience, as falling ice and rock from the upper crown are a constant hazard throughout most of the year. Weather on Mount Rainier can shift fast, so careful planning and ongoing attention to conditions are essential before and during any attempt.

The Carbon Glacier basin beneath the wall is constantly reshaped by ice movement and avalanches, meaning the conditions a climber finds one season can be markedly different from the next. What looks like a fixed route one year may be partly gone or altered the following season.