I recently was directed to this terrific site, the Broer Map Library, that has high-quality scans of maps from all over the world from different eras.
This includes the eight states that carried Route 66, which can be found at an index here. The Broer collection is a great resource for highway researchers. You can see how roads evolved. And the zoom feature works very well.
For instance, in this 1895 map of Illinois, you’ll notice that few of the roads are named. It looks like a bunch of lines, with little to differentiate one road from another. No wonder people got lost.
In this 1926 map of Oklahoma (an excerpt is at right), you’ll notice that the road that became U.S. 66 is listed as U.S. 60. That’s because the map was published before the designated numbers for national highways became final. The Chicago-to-Los Angeles highway boosters wanted U.S. 60, but highways officials in Kentucky objected. The designation of U.S. 66 was a compromise.
In the 1926 maps, you’ll also see that the future U.S. 66 was laid over existing roads, such as Postal Road, Ozark Trails, Lone Star Route, National Old Trails Road. You’ll also see a few towns that don’t exist anymore, like Boise, Texas; Pinevet, Ariz.; and Bannock, Calif.
Don’t be surprised if you blow an afternoon on this site.