If a county road is marked, a blue pentagon is used in all counties

Blue pentagons are not used in Maricopa County (Phoenix metro area)

Apache County has some blue pentagons (but they are rare)

Some of these CRs are also marked with a white square

Blue pentagons are used in NW Arkansas

Jasper in Newton County uses blue/gold on sign blades

California county roads are given a unique letter-number combination

A and B routes are in northern California

C and D routes are near the northern coast, but are not often marked

E routes are in and around Sacramento

G routes are near the central coast

J routes are in the central valley, south of Sacramento

N, R, and S routes are in southern California

Fremont Co, Ouray Co, and Routt Co use green squares

Douglas Co uses green pentagons

Florida county road numbers can have up to 4 digits

Many CRs have a number-letter combination

Occasionally a black pentagon is used instead of blue

Most IL county roads are marked with a both a number and a letter

Blue pentagons are sometimes used, but a numbered/letted blade is much more common

Rock Island County uses single/double letters instead of CR numbers

Blue pentagons are only used on I-80

Iowa uses blue pentagons in every county except Polk County

CRs use an alpha-numeric grid pattern based on location

Louisiana has Parish Roads instead of County Roads

The bottom text of signs will be "Parish" instead of "County"

Michigan uses both numbered County Roads and Intercounty highways

Intercounty highways are preceded by a letter based on state region

Older white squares do exist, but they are very rare or in gen 1 coverage

Michigan shield are more worn the farther north you go

Minnesota has an even distribution of blue pentagons and white squares

MN also has an "inter-county" system marked by single letters A to J

Diagonal braces can be used to identify Minnesota, when present

CR numbers are generally 3-digit and 4-digit, but some are 2-digit

Most of the northwest does not have CR coverage

Lettered county roads use white boxes with black borders

Numbered county roads use blue pentagons, but many do not have coverage

Missouri uses Farm Road (FR) in Greene, Barry, and Lawrence counties

Only Clark County uses blue pentagons, the rest are unsigned

New Jersey county roads are almost always in the 500s/600s/700s/800s

Bergen Co and Monmouth Co have a couple of CRs in the 100s

Some counties use green squares, some use blue pentagons

Schenectady Co uses a large sign with both local name and CR number

Ontario Co signs have the "RD" in a smaller font than the number

North Carolina does not have county roads, but Charlotte has city routes

Ashland Co has TWPs instead of CRs

Ohio has the greatest variation of signage, some examples are shown below

Click here to see the full state map

Blue pentagons can be found in Oregon, but are very rare

SD uses both blue pentagons and white squares somewhat sporadically

Some CR signs will use a number-letter combination

Most counties use Farm Roads instead of County Roads

Blue pentagons and squares are sometimes used near metro areas

All county roads are lettered instead of numbered