An alternate route northward from Hamel was opened in 1930. It followed IL 4 for , then branched off to the east, bypassing Staunton. The road moved northeast through Mount Olive past the Soulsby Service Station. The alignment from Litchfield to Mount Olive was added to the National Register of Historic Places on November 29, 2001. This segment is a stretch that begins northwest of Mount Olive in southeastern Macoupin County and ends about north of the intersection of US 66 and IL 16 in Litchfield. This alignment passed through North Litchfield, South Litchfield, Cahokia and Mount Olive townships. The terrain through the area is mostly flat. Unlike other sections of Route 66 in Illinois that are listed on the National Register, the segment from Litchfield to Mount Olive does not include any contributing structures such as bridges or culverts. The Ariston Café in Litchfield is the longest-operating restaurant along the former US 66. The Belvidere Café, Motel, and Gas Station also provided services to travelers. This alternate alignment continued north past Waggoner, Farmersville, Divernon, Glenarm and joined the original path in Springfield near the Old Capitol Building.