This 2.1 mile loop trail follows a restored section of the historic Columbia River Highway, which was constructed to route around the Tooth Rock (aptly named, for its shape). It then jogs right on a much older road, from the 1850s, before looping back to the beginning.
The first mile is along a restored section of the old Columbia River Highway, and feels a bit like walking on a freeway. Greenery and flowers decorate the way though, which makes it more pleasant. The old highway loops around Tooth Rock before arriving at Tooth Rock Viaduct. This impressive structure is thanks to Samuel Lancaster, the man who constructed the original historic highway.
Past the viaduct, the old highway crosses the modern freeway and meanders west back to the trailhead.
This trail climbs 315 ft and has several logs to easily cross over or go under. We saw wild ginger in this section of the loop. The return to the road is .2 miles from the TH parking lot. Wild geranium was profuse along the old HWY. Fringe cup an youth-on-age were also seen.