^Looking south at exit 33 for Illinois 4, near Staunton, 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.
The exit list starts in the south, at St. Louis, and will proceed going northward, as is typical for odd-numbered Interstate highways. Interstate 55 crosses into Illinois from Missouri via the Poplar Street Bridge, which also carries Interstate 64 and US Route 40...
Exit 1 provides access to Illinois 3's southern leg toward Cahokia; the state route joins Interstate 55, Interstate 64, and US Route 40 to the north and east:
Exit 1A splits from the ramp to exit 1, and it provides access to Tudor Avenue and 13th Street in East Saint Louis:
Exit 2A provides access to Barack Obama Avenue, the Eads Bridge, and the (unmentioned) western end of Illinois 15:
Exit 2B is only accessible from the southbound lanes, but it provides access to the MLK Bridge:
Exit 15A is for Illinois 159 south toward Collinsville, and this exit is part of a cloverleaf...
Exit 15B is the second half of the cloverleaf, leading to Illinois 159 north toward Maryville...
Exit 17 is a trumpet interchange allowing US Route 40 to split from Interstates 55 and 70, for travelers seeking out St. Jacob or Highland, Illinois...
Exit 23 accesses Illinois 143, taking travelers to Edwardsville or the town of Marine:
Exit 30 connects with Illinois 140, a road bringing people to Alton or Greenville:
Exit 33 connects to the north-south Illinois 4 from a diagonal northeastward Interstate 55, and Illinois 4 is indicated as the way to Staunton and Lebanon:
Exit 37 links travelers to Livingston and New Douglas (even though we are not in Livingston or Douglas County):
Exit 41 provides access to the town of Staunton, on the east side of that town:
Exit 44 leads to Illinois 138, which connects to Mt. Olive and Benld: