Grand Coulee Dam, at one time, was the largest dam in the world. The energy and agricultural irrigation resources provided by Grand Coulee Dam have been incredibly valuable to the entire North Central Washington State area. But, here are 7 Things You Don’t Know About: Grand Coulee Dam.

1. The Grand Coulee Dam is almost a mile long.
2. The original purpose of Grand Coulee Dam was to irrigate much of Central Washington, as World War II approached the primary use turned to the creation of electricity to assist in the war effort.
3. The reservoir behind Grand Coulee Dam is called Lake Roosevelt which stretches over 150 miles to the Canadian border.
4. Grand Coulee Dam actually creates two reservoirs, Lake Roosevelt and Banks Lake. Water behind Grand Coulee Dam is pumped uphill to fill Banks Lake which sits 280 feet above Lake Roosevelt.
5. Grand Coulee Dam is the largest concrete dam, and also the largest concrete structure, in North America.
6. The rising water behind Grand Coulee Dam forced the town of Kettle Falls to be relocated.
7. Initially the dam was planned to be shorter than it turned out to be, one of the reasons the design was changed to feature a taller dam was to create more jobs during the depression era.

Grand Coulee Dam has since been dwarfed by other dams around the world, but it remains a great accomplishment in history and a great place to visit.