Illinois Route 156 is a short east-west route in the southern part of the Metro-East. It basically serves as the main-west route in the Monroe County seat of Waterloo, and extends a bit farther east and west from there.
Illinois 156 will be described going from east to west. First, Illinois 156 begins at Illinois 13 near New Athens, as that route curves from a westerly direction to a northerly one...
Illinois 156 then encounters Illinois 159 north of Hecker, and it joins that route south for a while...
After the short concurrency along Illinois 159 south, Illinois 156 splits to continue westward on its own from Hecker...
After cutting through downtown Waterloo, Illinois 156 crosses Illinois 3...
Illinois 156 passes through Valmeyer and ends on the west side of town, becoming a rural road. This is just a couple miles east of the Mississippi River...