Leaving Naches and traveling west on the Chinook Scenic Byway, you will encounter basalt rock formations all along the Byway and the Naches River. These dark igneous rocks are the result of prehistoric lava flows that were composed of less than 53% silicon, which allowed them to flow long distances away from their source.
Basalt formations are frequently weathered to a reddish brown color or covered in algaes with different shades of red, green and yellow, creating colorful cliffs and protrusions that strongly contrast the sagebrush-dominated landscape. They also provide good riverside nesting for a variety of birds.
For more information on these basalt formations, see the Spokane Outdoors website