Quincy, Illinois, the seat of Adams County. It is about 95 miles (155 km) west of Springfield, on a bluff overlooking the Mississippi River. It is a trade and shipping center for a farming area that produces grains, livestock, and vegetables. The city's products include livestock feed, pumps, stoves, automobile and truck bodies, boat trailers, castings, brass products, storage tanks for gas, and electronic equipment. Riverboats use its harbor. Quincy University is located here.

Quincy was founded in 1822 and was an important river port in the mid-19th century. One of the Lincoln-Douglas debates was held here in 1858.

Population: 40,366.