Notes:
Highway Adoption is a volunteer road cleaning program
Most signs list the program logo above and volunteer below
Signs are usually found on smaller roads just outside cities
County program signs can differ from their states' design

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Alabama adoption sign

Alabama

Arizona adoption sign

Arizona

California adoption sign

California

Colorado adoption sign

Colorado

Connecticut adoption sign

Connecticut

Delaware adoption sign

Delaware

Florida adoption sign

Florida

Georgia adoption sign

Georgia

Georgia adoption sign

Georgia

Hawaii adoption sign

Hawaii

Idaho adoption sign

Idaho

Illinois adoption sign

Illinois

Indiana adoption sign

Indiana

Iowa adoption sign

Iowa

Kansas adoption sign

Kansas

Kentucky adoption sign

Kentucky

Louisiana adoption sign

Louisiana

Maryland adoption sign

Maryland

Massachusetts adoption sign

Massachusetts

Michigan adoption sign

Michigan

Minnesota adoption sign

Minnesota

Mississippi adoption sign

Mississippi

Missouri adoption sign

Missouri

Montana adoption sign

Montana

Nebraska adoption sign

Nebraska

New Hampshire adoption sign

New Hampshire

New York adoption sign

New York

New York adoption sign

New York

Rhode Island adoption sign

Rhode Island

South Carolina adoption sign

South Carolina

South Dakota adoption sign

South Dakota

Virginia adoption sign

Virginia

Washington adoption sign

Washington

West Virginia adoption sign

West Virginia

Wisconsin adoption sign

Wisconsin

Standard
Alaska adoption sign

Alaska

Arkansas adoption sign

Arkansas

Nevada adoption sign

Nevada

New Mexico adoption sign

New Mexico

North Carolina adoption sign

North Carolina

Oklahoma adoption sign

Oklahoma

Oregon adoption sign

Oregon

Pennsylvania adoption sign

Pennsylvania

Pennsylvania adoption sign

Pennsylvania

Texas adoption sign

Texas

Utah adoption sign

Utah

Wyoming adoption sign

Wyoming