With interstates, the numbering is just the opposite. The lower numbers are west and south. I-95 goes down the east coast, I-5 down the west coast, I-90 is up north and I-10 is down south. What about diagonal highways. They’re evens, apparently. I live near US 42, for instance, which runs diagonally (from Cleveland, OH to Louisville KY). So is US 62, from Niagara Falls to El Paso. In the 1960s the Saturday Evening Post contained a certain game: small close ups of national maps, and your job was to guess the location. If you knew something about the system of routes, the game was pretty fun.
Beginning around 1915, states began numbering their roads. Illinois developed a system, beginning with (but not limited to) several primary routes. There were four longitudinal roads. Illinois 1 is still there, except that the long curve from Norris City to Metropolis, originally part of route 1, is now part of US 45. Except for portions in the north, the original Illinois 2 is now US 51. Illinois 3 is still there, east and south of St. Louis, but north of St. Louis it’s now mostly US 67. Illinois 4 is still there, although it was originally a Chicago-St. Louis route, mostly replaced by the fabled US 66. (This c. 1920 postcard shows IL 2 meeting the National Road just east of my hometown.)
Several horizontal Illinois roads, too, were more or less in sequence north to south. Moving south, Illinois 5 (now US 20) went through Rockford, then 6 (the old Lincoln Highway, now Illinois 38), 7 (now US 6), then 17 through Kankakee (still there), 8 (now US 24), 9 (still there) through Bloomington, 10 (now mostly US 36) through Decatur and Springfield. The next west-east route, though, is Illinois 16 (still there), followed by Illinois 11 (the old National Road and now US 40) and 12 (now US 50). Then—still heading south—you have Illinois 15 through Mt. Vernon, 14 through Benton, and 13 through Marion and Carbondale.
I found this information at www.n9jig.com. The website www.us-highways.com has information about U.S. highways and also links to sites that describe roads in particular states.
Before roads were widely numbered, people relied upon AAA “Blue Books” to help them get around. You’d need a navigator every time you drove much distance in an unfamiliar territory! That’s because roads were imperfectly marked and followed zigzagging, sometimes informal paths. I’ve a copy of the 1915 AAA Blue Book. Here’s part of the directions if you were driving from St. Louis to Vincennes (p. 291):
66.2 7.3 4-corners, church and blacksmith shop on right; turn left and take first right crossing RR.
66.6 0.4 End of road; jog left and take first right, following poles.
70.2 3.6 End of road; turn right across RR. And immediately left, bearing right away from tracks. Go straight ahead into
75.9 5.7. Salem, Court House on left. Keep straight ahead cross R.R. 76.4. Road is direct with poles. Jog left and right, 77.2, winding through woods 81.5 past Xenia (on right—92.8)
That’s actually one of the easier routes!
I found physical evidence of a very old, winding road like this. If you take U.S. 51 north of Sandoval,
Locating very old alignments is interesting. Of course, many people like to discover and follow alignments of old Route 66. I also love to take U.S. 40 between Troy and Highland, where several stretches of old roadbeds, presumably from the late 1910s and the 1920s, still exist, although abandoned and overgrown, just north of the main road. I also found interesting roadbeds of U.S. 40 in Clark and Cumberland Counties, Illinois.
One time I found a highway bridge deep in timber. I was scouting the remains of a pioneer town, Old Loogootee in Fayette Co., Illinois. I found a few bricks from buildings, but I also found that narrow bridge fording a stream. There was little evidence of a road there, the old Vincennes Road that became state route 185. The bridge was haunting in its incongruity and abandonment.
A few years ago I found a wonderful book about landscape exploration, Outside Lies Magic: Regaining History and Awareness in Everyday Places by John R. Stilgoe, New York: Walker & Co., 1999. If a person is interested in evidences of 20th century American culture (not just roads but railroads and small town life), Stilgoe is a good author for ideas and inspiration!