Mount Washington, Mountain summit in White Mountains, New Hampshire, United States.

Mount Washington is the highest peak in the northeastern United States, rising 6,288.2 feet (1,916.6 meters) in New Hampshire's White Mountains. The summit is a broad, rounded dome of granite, snow-covered for much of the year, with a cluster of thin towers and masts at the top. A narrow road cuts a long diagonal line down the eastern slope, and the summit lies within a 60.3-acre state park surrounded by White Mountain National Forest.

The Abenaki people called this summit Agiochook before Darby Field became the first recorded European to reach the top in 1642. The Cog Railway opened in 1869 as the world's first mountain-climbing cog railroad and still carries visitors to the peak today.

The observatory on the summit welcomes visitors to its museum and visitor center, where staff explain their ongoing research on extreme weather. A small crew lives and works here year-round, enduring fierce storms and recording conditions that make this site famous among meteorologists.

Weather changes rapidly here and often brings strong winds and cold temperatures even in summer. Warm clothing and rain protection are necessary since fog and chill can appear at any moment.

The 231 mph (372 km/h) gust recorded on April 12, 1934, stood as the world record until 1996 and remains the highest measured wind speed not tied to a tornado or tropical cyclone. The summit's weather station, first built in 1870 by the U.S. Army Signal Service, was the world's first permanent mountaintop observatory.