Mount Washington, Extinct volcano in Cascade Range, Oregon, US.

Mount Washington is an extinct volcano in the Cascade Range with a prominent volcanic plug crowning its summit. Steep cliffs mark its sides, shaped by ancient lava flows that cooled and fractured over thousands of years.

Mount Washington formed during the late Pleistocene through subduction of the Juan de Fuca plate beneath the North American plate. Its last eruptions came from spatter cones about 1,350 years ago, producing basaltic andesite lava. A wagon road over McKenzie Pass was built in 1872 and paved in the 1930s, and the surrounding area became the Mount Washington Wilderness in 1964.

The mountain's name honors George Washington, first president of the United States. In the 1830s Hall J. Kelley proposed renaming the Cascade Range the Presidents' Range and giving each volcano a president's name; Mount Washington kept the name. The first ascent, on August 26, 1923, was made by six Bend high-school students: Ervin Mcneal, Phil Philbrook, Armin Fuhrer, Wilbur Watkins, Leo Harryman and Ronald Sellers. The Mazamas called it "an epochal event in northwest mountaineering".

The wilderness area features multiple hiking trails suitable for visitors with varying experience levels. Access is best during warmer months when snow and ice clear from the paths.

Mount Washington's summit plug makes it resemble Cleopatra's Needle from some angles and Brazil's Sugarloaf Mountain from others. Its first ascent, on 26 August 1923, was made by six Bend high-schoolers, one of whom slipped and nearly fell more than 200 metres; the Mazamas called the climb an epochal event in northwest mountaineering.