This area along the Columbia River preserves a history of dramatic change, from a once lowland landscape lush with plant life before the Cascade Mountains formed to the drier Columbia Plateau of today. Many kinds of trees, including Ginkgo, once grew on nearby hills and were uprooted and soaked by flood waters before settling to the bottoms of lakes. Roughly 12 to 17 million years ago, silica-enriched lava poured from cracks in the earth and spread across 63,000 square miles, burying this area; when one flow entered an ancient lake here, lava cooled around water-soaked logs and silica slowly replaced the trees’ organic cells, transforming them over time into the petrified forest of Ginkgo State Park. As the Cascade Mountains rose, central Washington’s moist climate became drier, yet life continued to flourish on the arid plateau in sagebrush-covered hills, nocturnal summer wildlife, abundant deer and elk, and reptiles basking in the sun.