Headed up to the Mt Hood area for New Year's and hiked Castle Canyon via the West Zigzag Mountain trailhead which added a pleasant, easy stroll before climbing steeply up Castle Canyon.
After checking out the Pinnacles Viewpoint we decided to explore the trail heading northwest from the saddle above the viewpoint. There was an even better viewpoint with a sketchier approach and steep dropoff.
When our hike was over I finally read other posts on Castle Canyon, one of which mentions the second ridge.
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On our way down we explored some of the side trails mentioned in the field guide, one of which brought us back to the closed section of the road back to our trailhead. We avoided 0.2 miles of road walking but had to navigate blowdown, so it didn't save us any time.