I have to second what [MENTION=23800]glg[/MENTION] posted. I have driven in to the city (I live about 10 minutes NW of ORD) and it has taken me as much as 90 - 120 minutes just to get to the Loop (Chicago's downtown). So taking the seemingly shorter and cheaper route through the city could add an extra hour or more depending on traffic. You an always use a Nav app like Waze or Google Maps to help make the decision as both are fairly accurate as to current traffic and conditions.