From Stevenson, WA: Travel east on Washington State Route 14 for 10 miles. Trailhead parking is available at milepost 53.7...look for the Dog Mountain Trailhead sign.
From Portland, OR: Travel east on Interstate 84 to Cascade Locks exit #44. Follow the off ramp under the interstate and take the first right to the Bridge of the Gods across the Columbia River. At the stop sign, turn right (east) on Washington State Route 14 and travel 12 miles. At milepost 53.7 there is a large sign for the Dog Mountain Trailhead. Park in the pullout on the left.