Macomb is a city in and the county seat of McDonough County, Illinois, United States. It is situated in western Illinois, southwest of Galesburg. The city is about 75 miles (121 km) southwest of Peoria and 77 miles (124 km) south of the Quad Cities. A special census held in 2014 placed the city's population at 21,516. Macomb is the home of Western Illinois University.

Moline ( moh-LEEN) is a city located in Rock Island County, Illinois, United States. With a population of 43,977 in 2010, it is the largest city in Rock Island County. Moline is one of the Quad Cities, along with neighboring East Moline and Rock Island in Illinois and the cities of Davenport and Bettendorf in Iowa. The Quad Cities have an estimated population of 381,342. The city is the ninth-most populated city in Illinois outside the Chicago Metropolitan Area. The corporate headquarters of Deere & Company is located in Moline, as was Montgomery Elevator, which was founded and headquartered in Moline until 1997, when it was acquired by Kone Elevator, which has its U.S. Division headquartered in Moline. Quad City International Airport, Niabi Zoo, Black Hawk College, and the Quad Cities campus of Western Illinois University-Quad Cities are located in Moline. Moline is a retail hub for the Illinois Quad Cities, as South Park Mall and numerous big-box shopping plazas are located in the city. In the mid-1990s, the city undertook major efforts to revitalize its central business district, which had declined after suburban growth and retail changes after the 1950s and 1960s. Today, Moline's downtown again serves as one of the civic and recreational hubs of the Quad Cities; many events take place at the 12,000-seat TaxSlayer Center (formerly known as The MARK of the Quad Cities and iWireless Center) and at John Deere Commons. Downtown Moline features hotels such as Radisson, The Element Moline, The Axis Hotel, and Stoney Creek Inn, along with commercial areas such as Bass Street Landing and the historic 5th Avenue. Moline acquired its name after it was platted (surveyed and planned) in 1843. The name derives from the French moulin meaning "mill town".

Davenport is a city in and the county seat of Scott County, Iowa, United States. It is located along the Mississippi River on the eastern border of the state, and is the largest of the Quad Cities, a metropolitan area with a population estimate of 382,630 and a CSA population of 474,226; it is the 90th largest CSA in the nation. Davenport was founded on May 14, 1836 by Antoine Le Claire and was named for his friend George Davenport, a former English sailor who served in the U.S. Army during the War of 1812, served as a supplier Fort Armstrong, worked as a fur trader with the American Fur Company, and was appointed a quartermaster with the rank of colonel during the Black Hawk War. According to the 2010 census, the city had a population of 99,685 (making it Iowa's third-largest city). The city appealed this figure, arguing that the Census Bureau missed a section of residents, and that its total population was more than 100,000. The Census Bureau estimated Davenport's 2019 population to be 101,590.Located approximately halfway between Chicago and Des Moines, Davenport is on the border of Iowa across the river from Illinois. The city is prone to frequent flooding due to its location on the Mississippi River. There are two main universities: St. Ambrose University and Palmer College of Chiropractic, where the first chiropractic adjustment took place. Several annual music festivals take place in Davenport, including the Mississippi Valley Blues Festival, the Mississippi Valley Fair, and the Bix Beiderbecke Memorial Jazz Festival. An internationally known 7-mile (11 km) foot race, called the Bix 7, is run during the festival. The city has a Class A minor-league baseball team, the Quad Cities River Bandits. Davenport has 50 plus parks and facilities, as well as more than 20 miles (32 km) of recreational paths for biking or walking. Three interstates, 80, 74 and 280, and two major United States Highways serve the city. Davenport has seen steady population growth since its incorporation. National economic difficulties in the 1980s resulted in job and population losses. The Quad Cities was ranked as the most affordable metropolitan area in 2010 by Forbes magazine. In 2007, Davenport, along with neighboring Rock Island, won the City Livability Award in the small-city category from the U.S. Conference of Mayors. In 2012, Davenport, and the Quad Cities Metropolitan Area, was ranked among the fastest-growing areas in the nation in the growth of high-tech jobs. Notable natives of the city have included jazz legend Bix Beiderbecke, Pulitzer Prize-winning playwright Susan Glaspell, former National Football League running back Roger Craig, UFC Welterweight Champion Pat Miletich, IBF Middleweight and WBA Super Middleweight boxing champion Michael Nunn, and former two time WWE Champion and WWE Universal Champion Seth Rollins.

Peoria ( pee-OR-ee-ə) is the county seat of Peoria County, Illinois, and the largest city on the Illinois River. As of the 2010 census, the city had a population of 115,007. It is the principal city of the Peoria Metropolitan Area in Central Illinois, consisting of the counties of Marshall, Peoria, Stark, Tazewell, and Woodford, which had a population of 373,590 in 2011. Established in 1691 by the French explorer Henri de Tonti, Peoria was later labeled by the Peoria Historical Society to be the oldest European settlement in Illinois. Originally known as Fort Clark, it received its current name when the County of Peoria organized in 1825. The city was named after the Peoria tribe, a member of the Illinois Confederation. On October 16, 1854, Abraham Lincoln made his Peoria speech against the Kansas-Nebraska Act.A major port on the Illinois River, Peoria is a trading and shipping center for a large agricultural area that produces corn, soybeans, and livestock. Although the economy is well diversified, the city's traditional manufacturing industries remain important and produce earthmoving equipment, metal products, lawn-care equipment, labels, steel towers, farm equipment, building materials, steel, wire, and chemicals. Until 2018, Peoria was the global and national headquarters for heavy equipment and engine manufacturer Caterpillar Inc., one of the 30 companies composing the Dow Jones Industrial Average, and listed on the Fortune 100; in the latter year, the company relocated its headquarters to Deerfield, Illinois.The city is associated with the phrase "Will it play in Peoria?", which originated from the vaudeville era and was popularized by Groucho Marx. Museums in the city include the Pettengill-Morron House, the John C. Flanagan House, and the Peoria Riverfront Museum.