- 511PA
- AA Roads-Pennsylvania Gateway - Andy Field/Alex Nitzman
- American Society of Highway Engineers-Altoona Section
- American Road Magazine
- America's Byways-Pennsylvania - Federal Highway Administration
- Associated Pennsylvania Constructors
- Cat Scale
- Commonwealth of Pennsylvania
- Delaware River Joint Toll Bridge Commission
- Drive Clean Pennsylvania-Vehicle Emissions Inspection and Maintenance
- Federal Highway Administration: Pennsylvania Division
- Historic Bridges of the U.S.-Pennsylvania - James Baughn
- Intelligent Transportation Society of Pennsylvania
- Just Drive PA
- Keep Pennsylvania Beautiful
- Larson Transportation Institute - Penn State University
- Mothers Against Drunk Driving: Pennsylvania State Organization
- PAHighways Clinched Highways - See the routes I have traveled end-to-end.
- Pennsylvania AAA Federation
- Pennsylvania Aggregates and Concrete Association
- Pennsylvania Asphalt Pavement Association
- Pennsylvania Code - Title 67 Transportation
- Pennsylvania Department of Motor Vehicles
- Pennsylvania Department of Transportation (PennDOT)
- PennDOT District 1 (Crawford, Erie, Forest, Mercer, Venango, Warren)
- PennDOT District 2 (Cameron, Centre, Clearfield, Clinton, Elk, Juniata, McKean, Mifflin, Potter)
- PennDOT District 3 (Bradford, Columbia, Lycoming, Montour, Northumberland, Snyder, Sullivan, Tioga, Union)
- PennDOT District 4 (Lackawanna, Luzerne, Pike, Susquehanna, Wayne, Wyoming)
- PennDOT District 5 (Berks, Carbon, Lehigh, Monroe, Northampton, Schuylkill)
- PennDOT District 6 (Bucks, Chester, Delaware, Montgomery, Philadelphia)
- PennDOT District 8 (Adams, Cumberland, Dauphin, Franklin, Lancaster, Lebanon, Perry, York)
- PennDOT District 9 (Bedford, Blair, Cambria, Fulton, Huntingdon, Somerset)
- PennDOT District 10 (Armstrong, Butler, Clarion, Indiana, Jefferson)
- PennDOT District 11 (Allegheny, Beaver, Lawrence)
- PennDOT District 12 (Fayette, Greene, Washington, Westmoreland)
- Pennsylvania DUI Association
- Pennsylvania Highway Beautification Program
- Pennsylvania Highway Information Association
- Pennsylvania License Plates - Bruce Bufalini
- Pennsylvania Motor Truck Association
- Pennsylvania One Call System
- Pennsylvania Road Photos and more... - Adam Prince
- Pennsylvania Roads - Steve Alpert
- Pennsylvania Roads - Rachel Aschmann
- Pennsylvania's Roads - Pennsylvania Historical and Museum Commission
- Pennsylvania Scenic Byways
- Pennsylvania State Police
- Pennsylvania Tourism Signing Trust
- Pennsylvania Turnpike Commission
- Pennsylvania Windshield Inspection Stickers 1969-Present - Bruce Bufalini
- Posted and Bonded Roads - PennDOT
- RV Dump Stations in Pennsylvania - Roundabout Publications
- SWPA Roads Project - Adam Prince
- USA Traffic Signs
- VisitPA
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