Figure 4 shows the important points along the railroad. Mentally roll the paper into a tube and place yourself inside the tube. Weehawken is in the lower right and traffic to Scranton moves to the left and up until the upper left hand corner is reached. Locations have been pushed or pulled to or from Weehawken to meet certain constraints. For instance, yards have to be on odd numbered laps as discussed above. Trestles have to be on even numbered laps to be four inches higher than the terrain in front.