Des Plaines is a city in Cook County, Illinois, United States. It has adopted the official nickname of "City of Destiny." As of the 2000 census. It is a suburb of Chicago, and is next to O'Hare International Airport. The Des Plaines River runs through the city, just east of its downtown area. According to the United States Census Bureau, the city has a total area of 14.5 square miles (38km2).Of this, 14.4 square miles (37km2) of it is land and 0.1 square miles (0.26km2) of it (0.76%) is water.