CPKC Prairie Hill Road Bridge

In 1880, the Janesville, Beloit and Rockford Railway (JB&R) constructed 14 miles of new railroad, extending from Janesville, Wisconsin to Beloit, Wisconsin.  At Beloit, it intersected with an existing railroad line owned by the Chicago, Milwaukee & St. Paul Railway (Milwaukee Road).  The following year, the Central Illinois and Wisconsin Railway (CI&W) constructed an additional 15 miles to Rockford.  The JB&R was sold to the Milwaukee Road in 1882, and the C&IW was leased to the Milwaukee Road the same year.  Via trackage rights over the Chicago, Burlington & Quincy Railroad between Rockford and Davis Junction, this line connected to the Milwaukee Road mainline from Chicago to Omaha.  The C&IW was purchased by the Milwaukee Road in 1900.

By the 20th Century, the Milwaukee Road had become a prominent railroad in the United States, operating a network of railroad lines primarily in the Midwest.  This line primarily served to connect lines in Wisconsin to the Chicago to Omaha line, as well as serve industries along the Rock River.  The Milwaukee Road was often in financial trouble, especially after the costly Pacific Extension was completed in 1909. In 1925, the company declared bankruptcy, and reorganized as the Chicago, Milwaukee, St. Paul and Pacific Railroad in 1928.  By 1985, a suitor for the Milwaukee Road was being sought, and the Soo Line Railroad, controlled by Canadian Pacific Railway (CP) purchased the Milwaukee Road in 1986.  In 1997, CP would sell the line segment to I&M Rail Link, which was later purchased by the Dakota, Minnesota & Eastern Railroad (DM&E) subsidiary Iowa, Chicago & Eastern Railroad (IC&E).  The DM&E/IC&E were purchased by Canadian Pacific in 2008.  The CTR trackage was abandoned in 2018.  CP merged with Kansas City Southern Railway in 2023 to form CPKC.  Today, CPKC operates the Rockford Subdivision between Janesville and Rockford, with a connection to Davis Junction.