Completed 1942, the 550-foot-tall concrete structure stretches 5,223 feet long. The largest hydropower producer in the country, the dam can generate more than 21 billion kilowatt-hours of electricity each year, or enough to supply about 2 million homes with electricity.

The Grand Coulee Dam also provides irrigation to a half million acres of arid land.

Explore the Grand Coulee Dam

Visit the dam’s power plant between April and October to see some of the largest turbines in the world, then take a van ride across the concrete monolith and gaze out to where the 151-mile long Lake Roosevelt stretches out to the horizon.

During the summer months, stick around late into the night for a narrated laser light show that splashes color across the face of the dam and tells the story of how, and why, the Grand Coulee Dam was constructed. The show is free and lasts around 30 minutes.