Cowlitz River—Castle Rock to Longview Professional Guide
Detailed Trail Description from our Guidebook
"This trip follows the Cowlitz River on the last leg of its journey to the Columbia. The trip starts in the town of Castle Rock and ends near the mouth of the Cowlitz in Longview.
The entire trip is downstream from where the Toutle River joins the Cowlitz. As a result, this stretch of the Cowlitz is lined with volcanic ash and sand from the effects of the eruption of Mount St. Helens in 1980."