Yerrinbool
As we get closer to Sydney, the Southern Highlands constricts down to a narrow spit of cleared land nestled between the Blue Mountains on the west and the Upper Nepean gorge on the east, and almost all of the transport infrastructure squeezes into a narrow 500m-wide band between Yerrinbool and Bargo. This limits the room available for deviations but also gives us a choice of several existing corridors to utilise.