Keystone Lake is a reservoir in northeastern Oklahoma on the Arkansas and Cimarron rivers.

[3] The primary purposes are: flood control, hydroelectric power generation, wildlife management and recreation.

The town of Osage was partially abandoned to the lake, while the rest clings to the south shore.

Engineers built a levee around low-lying areas of the south and east sides of Cleveland, Oklahoma to prevent flooding of that city.

The area also features a Yogi Bear's Jellystone Park Camp-Resort as you cross the Keystone Dam near Sand Springs.

[4] In September and October 1986, Keystone Lake was filled to capacity when the remnants of Hurricane Paine entered Oklahoma and dropped nearly 22 inches (0.56 m) of water into the Cimarron and Arkansas rivers northwest of the lake, requiring the Corps of Engineers to release water downstream at a rate of 310,000 cubic feet per second (8,800 m3/s), which made downstream flooding inevitable.

As a result, a private levee in West Tulsa failed, causing more than $1.3 million in damages.

[6] Fauna around the lake include: white-tailed deer, raccoon, bobcat, coyote, beaver, squirrel, cottontail rabbit, quail, dove, ducks and geese.