High Quality Content by WIKIPEDIA articles! Quadrant Routes in Pennsylvania are maintained by PennDOT. This article lists all the routes and their termini in Columbia County. As is the case with the other counties in the state, the route numbers start in the northeast quadrant and go clockwise from the 1000s to the 4000s. There is no numbering order scheme. Odd numbered roads travel south to north. Even numbered roads travel west to east.