This past September I spent some time out in northern Oregon. That being the case I had a chance to drive the modern Columbia River Highway/US 30 from Astoria east to Portland and a segment of the Historic Columbia River Highway east of Troutdale. While I don't think I'm hitting on much in the way of new territory with the history of the Columbia River Highway I did include numerous historical maps and documents in the blog below along with two lengthy driving features. Of note the Columbia River Highway appears to have been signed in parts with at least four Auto Trails; Grant Highway, Theodore Roosevelt International Highway, Old Oregon Trail, and California-Banff "B" Line.
https://www.gribblenation.org/2019/12/us-route-30columbia-river-highway-old.html