From Clarkston Washington, take Highway 129 to Asotin. From Asotin head to Anatone and down Rattlesnake Grade on Highway 129. Go past Field Springs State Park to where Highway 129 crosses the Grande Ronde River at Boggans Cafe. From the Oregon side take Highway 129 from Enterprise to where Highway 129 crosses the Grande Ronde River.
Directions to the Moses Lake/Potholes Reservoir:
Moses Lake is located between Ellensburg and Spokane on I-90. From west of the Cascade Mountains, take I-90 eastbound. From the Spokane area, take I-90 westbound.
Potholes Reservoir is located just south of Moses Lake. From exit 179 off I-90, take Highway 17 south. Turn right off Highway 17 onto Road "M" and continue south to the stop sign/"T" in the road. Take a right at the "T" and continue over the dam to Potholes Reservoir.