The park takes its name from the landscape's dominating feature, Steamboat Rock, a basalt butte that rises 800 feet (240 m) above the lake which nearly completely surrounds it.

[2] The butte's plateau covers more than 600 acres (240 ha) and was used by nomadic Native American tribes and by early settlers.

Once the dams burst creating massive floods and the Scablands, the Columbia returned to its original course, leaving Steamboat Rock as a prominent feature of the dry Grand Coulee.

[2] The park has 50,000 feet (15,000 m) of shoreline and is open year-round for camping and day use.

The park has trails for hiking, biking, and equestrian use as well as water activities including boating, swimming, waterskiing, and fishing.