Mount Rainier (14,411 feet) is the highest peak in Washington, and 5th highest in the conterminous USA. There are many great routes on Rainier, and any ascent is a true classic. The most commonly-climbed route is the Disappointment Cleaver from the Paradise parking lot, via Camp Muir and Ingraham Glacier. The route requires glacier travel and around 9,000 feet of altitude gain.