Some saw a numbered highway system as cold and heartless compared to the more colorful names of the auto trail systems.

He didn't know where it was going, but he was an expert in sticking to an auto trail without betraying his own presence.

In the age of the auto trail, the roads that later formed US 2 through the UP were given a few different highway names.

One Canadian auto trail was routed through the UP as well.

And rather than designate one number for each auto trail, different sections of each trail were given different numerical designations.

The route did not directly replace any auto trail, instead combining portions of many into one continuous route.

Dixie Highway was named as a part of the original auto trail of the same name.

This auto trail went on a direct route between Minneapolis and Yellowstone National Park.

The route was originally designated as an auto trail named the Southern Minnesota Air Line in a 1919 application.

The "Swastika Trail" is a historic auto trail in Iowa.