Illinois Route 156Illinois Route 156 is an east-west state road in southwestern Illinois. It runs from South Meyer Avenue & C Road in Valmeyer to just west of New [Athens, Illinois|New Athens]. This is a distance of.Route descriptionIllinois 156 runs through rural southwestern Illinois. It is the main east-west state road through Waterloo. Illinois 156 overlaps Illinois Route 159 from Hecker north for a short distance, when 156 leaves 159 and turns back toward its eastern terminus.HistorySBI Route 156 is the same as Illinois 156 is now. There have been no changes since 1926.