Your hometown's sign has a part number, and it depends who you ask
In the federal sign manual, the sign at the edge of your hometown is called I2-1.
That's its whole name as far as Washington is concerned. Every sign on an American road has a code like that, and once you know how to read one, you can't stop seeing the filing system behind the windshield.
How to read a sign code
The Manual on Uniform Traffic Control Devices sorts signs into families, and the letter tells you the family. R is regulatory, the signs that can get you a ticket. W is warning. I is general information.
The number before the dash is the group, and the number after it is the specific sign. So:
| Code | Sign |
|---|---|
| R1-1 | STOP |
| R1-2 | YIELD |
| R2-1 | Speed Limit |
| W8-13 | BRIDGE ICES BEFORE ROAD |
| M1-1 | The Interstate shield |
| I2-2 | The sign that names the river you're crossing |
| I2-1 | Your hometown |
The manual's own name for I2-1 is the Jurisdictional Boundary sign. Not much romance in that.
What the federal book allows on it
The current edition, published in December 2023, is strict about I2-1. The sign has to be a rectangle with white lettering on green. It "shall display only the name" of the place and a short legend, like ENTERING or the kind of municipality it is.
A town can add its official seal, on the left, no taller than twice the height of the first capital letter. Somebody measured that.
And then there's a line aimed squarely at civic pride. Names of elected officials and "promotional messages, such as notable accomplishments or claims," are not allowed on the sign. No mayor. No state champs. Not on this one.
Every state renumbered it anyway
States adopt the federal manual, then keep their own catalogs. The same green rectangle gets a different part number depending on whose filing cabinet you open.
In Missouri, the city limit sign is I4-1, and the version with the town seal is I4-1a. So the sign on a state highway into Hannibal is filed under I4. In the federal book, I4-1 is the sign for a library.
California calls its version G9-5(CA). The sign for a town that never incorporated is G9-2(CA). Colorado's layout, the one with the elevation on it, is D50-3.
Wisconsin's catalog lists the "Community Population Name Sign" as I-2-1-P, and the unincorporated version as I-2-1-U. Ohio adds two little signs of its own: ENTER CORP, which is I-H2b, and LEAVE CORP, which is I-H2c. They come in a twelve-inch size for tight spots.
We got this one wrong
An earlier story of ours said the standard city limit sign was I4-1. That's Missouri's number, not the federal one. We were reading Missouri's manual at the time and took its catalog for everybody's. It's fixed now.
In our defense, the people who write these can't agree either.
Nobody calls it that
Somewhere in a state sign shop there's a work order with your town's name typed next to a code. Somebody made the sign, and a crew bolted an I2-1 to a post by the side of the road.
Then you drove past it about four thousand times and never once called it that.