Street, IL 1 meets IL 15, which connects to State Route 64 (SR 64) in Indiana. Continuing northeast, IL 1 and IL 15 run concurrently to the junction of North Market Street, where they turn northwest to the intersection with East Ninth Street. There, IL 1 and IL 15 split in different directions, with IL 15 heading southwest while IL 1 runs northeast on East Ninth Street. The route continues on East Ninth Street for two blocks, where the road turns northwest on North Cherry Street. Along North Cherry Street, IL 1 turns north and winds out of Mount Carmel. IL 1 turns northeast north of Mount Carmel and returns to its parallel with the Wabash River. The road passes the village of Allendale before crossing the line into Lawrence County. At the community of Sand Barrens, IL 1 passes east of the Mount Carmel Municipal Airport and west of the village of St. Francisville. The route continues straight north until reaching the village of Lawrenceville. In Lawrenceville, IL 1 is known as 15th Street. At State Street, the route junctions with US 50 Business, which connects to IL 250 and US 50. After leaving downtown Lawrenceville, the route meets US 50 at a grade-separated interchange. For the next , IL 1 continues straight north, reaching the Crawford County line near the community of Birds. Robinson to Hoopeston Passing to the east of the city of Robinson, IL 1 reaches a junction with IL 33. Meeting at the community of Gordons, IL 33 also connects to the village of Palestine. Several miles north, the route reaches Clover Street, which runs east in the village of Hutsonville, where it becomes Indiana's SR 154. Continuing north, IL 1 passes Lake Walton and crosses into Clark County. Through Clark County, the road makes several bends in various northern directions before reaching the city of Marshall. In Marshall, IL 1 is known as South Sixth Street before becoming Michigan Avenue. At the northern end of the city, IL 1 junctions with US 40. After crossing railroad tracks, IL 1 then meets Interstate 70 (exit 147). After Marshall, IL 1 continues north and crosses into Edgar County. The route soon reaches the city of Paris, where it becomes South Main Street. After Jackson Street, the route becomes a one-way pair, with the northbound direction running along Main Street while the southbound directions runs on Monroe