Illinois Route 336 (IL 336, also known as the Thomas A. Oakley Memorial Highway) is a four-lane freeway/expressway combination that serves western Illinois. It is also used by the Illinois Department of Transportation (IDOT) as a part of Federal-Aid Primary Highway 315 (FAP315) to refer to a future project connecting the cities of Quincy and Peoria via underserved Macomb. As of early 2018, the highway extends north from its starting point in Fowler (near Quincy) where U.S. Route 24 (US 24) and Interstate 172 (I-172) intersect, to US 67 just north of Macomb. IL 336 is 80 miles (129 km) long.