Greenleaf Peak is a 3,424-foot mountain in the southern Washington Cascades above the Columbia River Gorge, near Table Mountain and Bonneville Dam. It is significant both for its dramatic setting and for exploration history: in September 1825, botanist David Douglas climbed its summit in what is regarded as the first recorded mountain ascent in present-day Washington. Its geology is equally notable. Red Bluffs exposes part of the unstable Eagle Creek formation that has repeatedly collapsed, contributing to the Cascade Landslide Complex, including the Bonneville Slide that formed the Bridge of the Gods and Cascade Rapids. The area remains active, with a major landslide occurring on the mountain’s south side in 2007–2008.