 The first interchange is for IL 3, which heads south toward Cahokia; the interstate has an interchange with I-64 towards Fairview Heights, and I-55, which it joins and heads northeast.Previously, I-70 ran together with I-55 and I-64 across the Poplar Street Bridge downstream, crossing into East St. Louis; when it was realigned to the current routing, the section through downtown St. Louis was absorbed into another interstate.I-55/I-70 have an interchange with IL 203 before entering Madison County.