Joliet ( ) is a city in Will and Kendall counties in the U.S. state of Illinois, southwest of Chicago. It is the county seat of Will County. At the 2020 census, the city was the third-largest in Illinois, with a population of 150,362. History In 1673, Louis Jolliet, along with Father Jacques Marquette, paddled up the Des Plaines River and camped on a huge earthwork mound, a few miles south of present-day Joliet. Maps from Jolliet's exploration of the area showed a large hill or mound down river from Chicago, labeled Mont Joliet. The mound has since been flattened due to mining. In 1833, following the Black Hawk War, Charles Reed built a cabin along the west side of the Des Plaines River. Across the river in 1834, James B. Campbell, treasurer of the canal commissioners, laid out the village of "Juliet", a corruption of "Joliet" that was also in use at the time. Just before the economic depression of 1837, Juliet incorporated as a village, but to cut tax expenses, Juliet residents soon petitioned the state to rescind that incorporation. In 1845, local residents changed the community's name from "Juliet" to "Joliet", reflecting the original name. Joliet was reincorporated as a city in 1852. Cornelius Covenhoven Van Horne was active in getting the city its first charter, and because of this, he was elected Joliet's first mayor. When the city later built a new bridge, it was named the Van Horne Bridge. Geography According to the 2010 census, Joliet has a total area of , of which (or 98.95%) are land and (or 1.05%) is covered by water. It has a sprawling, irregular shape that extends into nine different townships, more than any other Illinois city. They are: Joliet, Plainfield, Troy, New Lenox, Jackson, Channahon, and Lockport in Will County, and Na-Au-Say and Seward in Kendall County. Joliet developed along the Des Plaines River, and its downtown is located in the river valley. Joliet has a "west side" and "east side", referring to areas in relation to the river. With the construction of highways and suburban development to the west, many businesses moved from the downtown area to the expanding areas west of the river. Many stores relocated to the west side in new strip malls and shopping centers with more parking and easier access. These changes resulted in the decline of the downtown shopping district, which is