The park is an area of exposed petrified wood and logs, which grew as far back as the Miocene epoch. The existence of the petrified wood was discovered during highway construction in the early 1930's. Common among the wood remains are pieces of petrified ginkgo, a tree which previously grew in the area. The ginko exists now only as a specimen tree and grows nowhere in the wild. There is also a collection of Native American petroglyphs within the park.
The 7500-acre park is on the Wanapum Reservoir on the Columbia River and features a variety of activities including hiking, camping, water skiing and an interpretive center.
The Washington State Parks system includes more than 125 developed parks and covers about a quarter million acres.