^Southbound trailblazer leading away from Illinois 10 (exit 126) in Lincoln, February 2022.
Interstate 55 begins in Chicago along Lake Shore Drive (US Route 41) and heads southwest along the former route of US Route 66, crossing the Mississippi River into St. Louis, Missouri. It passes along Joliet's western flank and connects to Normal, Bloomington, and Springfield before it reaches the St. Louis metroplex.
Exit 154 is for Shirley, connecting to McLean County Highway 34:
Exit 157A is part of an interchange where Interstate 74 and US Route 51 join Interstate 55 north around the west side of Bloomington-Normal; this first exit accesses Interstate 74 east and US Route 51 south (toward Indianapolis or Decatur):
Exit 157B provides access to the southern beginning of Business Loop 55 through Bloomington (the southbound way to this exit forces you to take the ramp to I-74 east first):