I stopped at the Pendleton Woolen Mills Store and was intrigued by a tunnel under Highway 14. This tunnel took me to the dike path that runs from Steamboat Landing Park (next to the river side of the tunnel) to Captain William Clark Park, and further to Steigerwald Lake National Wildlife Refuge.
For this walk, you could either park at the Pendleton Store or at Steamboat Landing Park.
Petroglyph replicas in the tunnel from Washougal to the river. 
to Captain William Clark Park along the dike path 
Pathway from the dike path to downtown Washougal. 
Dike path along the Columbia River 
Gateway to the Columbia River
