This is the Monroe Avenue bridge over the Kennedy Expressway, as it enters the city from the north. As this is the main expressway into the city from the northern suburbs, the traffic is constant.
Chicago's traffic can get pretty bad...especially in the summer. In addition, there are several highway road construction projects that will cause driving delays through the end of the summer.
The traffic in Chicago is horrible so riding a bike, rollerblading or just walking are probably the best ways for getting around. :-)