Cougar Mountain is a 1,614-foot peak in the Issaquah Alps on Seattle’s Eastside, the lowest and westernmost of those forested hills. Though much of it rises above developed neighborhoods and about two-thirds has seen residential growth, it still retains a substantial protected core. Its summit area offers views of Seattle, Mercer Island, Lake Washington, and the Olympic Mountains. The mountain was formed through tectonic uplift and erosion that exposed older sedimentary and volcanic rocks, and its northern edge is shaped by the Seattle Fault, source of a major earthquake about 1,100 years ago. Today it combines preserved habitat, parkland, recreation, and regional infrastructure.