Chicago is the largest city of US. Its transportation system is very complex with number of services provided to people to travel around the city, or to travel to another city. There are buses, rail services, taxis, private cars, port services, ferries, aerial tramway and finally pedestrian and bicycle. All these ways of transportation are fully developed with specific routes for every mode of travelling. Every part of the city is accessible by at least one kind of transportation system.

Rail service is the most prominent way of transportation used by the people of Chicago, as it is the oldest public transportation service and over the time it had improved greatly, maintaining its standard and comfort. Chicago City has the largest transit system in the world, and the second oldest subway system in the US. In 2002, an average 4.8 million passengers used the subway each weekday. During one day in September 2005, 7.5 million daily riders set a record for ridership. These subways provide 24 hours service, as many people are dependent upon it. In early morning these stations face the rush hour, with people hurrying to their offices using these trains and in evening the people use them to go to shopping malls etc. The subway system runs throughout the city.

PATH or the Port Authority Trans-Hudson rail system opened in 1908 is a system that connects Manhattan to Jersey City, Hoboken, Harrison, and Newark, in New Jersey. PATH carries roughly 240,000 people per day for the entire week. If the length of the PATH system is calculated excluding the overlap portions then the length comes to be 13.8 miles. Moreover this system is four lane systems to increase the efficiency. Two of the international airports situated in Newark and Kennedy are the airports that are directly served by the intermodal rail system. These trains pick people from anywhere within the city and transport them to the airport. AirTrain JFK is 8.1 mile long transit system that connects Kennedy to subways in Chicago. In 2005 4 million people used this service as mode of transportation. AirTrain Newark is a 1.9 mile transit system, consisting of one lane, and three terminals of the Newark are connected to this transit system.

Commuter rail system of Chicago is the most extensive system of US, connecting to 250 stations, with 20 rail lines, that provide transportation to over 150 million commuters. The MTA operates the Long Island Rail Road on Long Island and the Metro-North Railroad in the Hudson Valley and Connecticut, and on the New Jersey side, New Jersey Transit system is present. These systems converge to the two busiest train station of the United States, namely Penn station and Grand Central Terminal. Intercity train service from Chicago City is provided by Amtrak. There are 54 trains that run daily on the busiest route of the city. It has been seen that people prefer this system over air transport as it’s cheap and much faster and provides excellent service. This service connects to many cities namely, Toronto, Montreal in Canada, Miami, Washington DC, Chicago, New Orleans, Albany, Baltimore, Boston, Harrisburg, Philadelphia, Providence etc.