city, seat (1839) of Rock county, southern Wisconsin, U.S. It lies on the Rock River, about 15 miles (25 km) north of Beloit and 40 miles (65 km) southeast of Madison. Settled in 1835 and named for a pioneer, Henry F. Janes, it developed as a trading centre for the surrounding agricultural region and as a manufacturing (agricultural equipment and writing instruments and later automobiles) and milling (lumber, flour, wool) centre. Automobile manufacturing is the basis of the modern economy; other products include automotive parts, machinery, plastics, textiles, electrical products, and room partitions. The city is also part of a major agricultural area, with crops that include soybeans, corn (maize), and tobacco.
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