[1] Botanist David Douglas climbed to the summit in September 1825, making this the first recorded mountain ascent in what is now Washington state.

[3] The propensity of the area south of Greenleaf Peak and Table Mountain to collapse in landslides is due to the Eagle Creek formation.

The rocks of the formation cover approximately 30 miles (48 km) of the Columbia River Gorge east of Cape Horn and consist of a mixture of past landslides, volcanic mud flows and ash falls.

Greenleaf Creek flows south through the basin before plunging as a waterfall over the Red Bluffs escarpment.

In the winter of 2007-2008, there was a large landslide on the south slope of Greenleaf Peak, in the state-owned Table Mountain Natural Resources Conservation Area.