Chicago is located in northeastern Illinois along the southwestern shores of Lake Michigan, at a continental divide connecting the Mississippi River and Great Lakes watersheds. Two major rivers—the Chicago River in downtown and the Calumet River on the South Side—flow through the city, shaping its industrial, transportation, and cultural development. Lake Michigan not only serves as a hub for commerce via Lake Calumet Harbor but also moderates the city’s climate, keeping waterfront neighborhoods warmer in winter and cooler in summer.

Founded in 1837 near the mouth of the Chicago River, the city is largely flat, with an average elevation of 579 feet above sea level. The lowest point lies along the lake shore at 578 feet, while the highest point is 672 feet at the Blue Island ridge in the far South Side. Chicago’s lakefront is home to iconic parks and public beaches, including Lincoln Park, Grant Park, Burnham Park, and Jackson Park. Landfill projects have created space for Navy Pier, Northerly Island, the Museum Campus, and parts of the McCormick Place Convention Center. Many of the city’s high-rise commercial and residential buildings cluster near the waterfront.

Chicago is informally known as “Chicagoland,” which encompasses the city and its surrounding suburbs. Within the city, major sections include the central business district, called the Loop, and the North, South, and West Sides. The North Side is densely populated with high-rises along the lakefront, while the South Side is the largest area, encompassing roughly 60% of the city’s land and housing much of the Port of Chicago. In the late 1920s, the University of Chicago’s sociologists defined 77 community areas, further subdivided into over 200 neighborhoods, creating the framework for understanding the city’s social and geographic diversity.

Chicago’s streets follow a grid system originating from the city’s original townsite. Arterial streets and residential blocks were planned for efficiency, with diagonal streets—many tracing old Native American trails—intersecting the grid. The city’s boulevards and parkways were inspired by the City Beautiful movement, creating a visually appealing urban landscape. Notable streets include Michigan Avenue, State Street, Western Avenue (the longest continuous urban street in the world), 95th Street, Cicero Avenue, Clark Street, and Belmont Avenue. In 2021, Chicago ranked as the fourth-most walkable large city in the United States, with many residential streets featuring landscaped sidewalks that provide a buffer from street traffic.

Chicago’s unique combination of waterways, parks, urban planning, and community organization reflects both its historic development and ongoing commitment to creating a livable, dynamic city.