Waukesha Subdivision
CN 3198, a GE ET44AC, in Duplainville on May 2, 2020.
Overview
Status	Active
Owner	Canadian National Railway
Locale	Wisconsin, Illinois
Termini	Fond du Lac Chicago
Service
Type	Freight, passenger
Operator(s)	Canadian National Railway, Wisconsin and Southern Railroad, Metra
History
Commenced	1882
Completed	1886
Technical
Number of tracks	1–2
Track gauge	4 ft 8+1⁄2 in (1,435 mm) standard gauge
Route map Legend north to Neenah Subdivision North Fond du Lac Neenah Subdivision Waukesha Subdivision 156.1 Fond du Lac to Eden Byron Hill 147.1 Byron 142.8 Lomira 138.3 Theresa 129.5 Allenton 122.6 Slinger Wisconsin and Southern Railroad Wisconsin and Southern Railroad 117.7 Rugby Junction UP Adams Subdivision 106.6 Sussex ←proposed flyover 102.6 Duplainville | CPKC Watertown Sub. ←proposed flyover ←proposed sidings 97.7 Waukesha ←proposed sidings 97.2 Wisconsin and Southern Railroad 90.9 Vernon 86.2 Mukwonago East Troy Electric Railroad 77.7 Honey Creek 72.7 Burlington 61.1 Silver Lake CPKC Hiawatha Connection Line to Sturtevant (proposed) 58.3 Trevor Wisconsin Illinois Metra Yard NCS ends 55.7 Antioch 50.7 Lake Villa 48.5 Round Lake Beach 46.5 Washington Street MD-N to Fox Lake to Union Station 43.4 Prairie Crossing 39.6 Mundelein to EJ&E/CN and BNSF Eola Yard / Mendota Sub. EJ&E/CN 35.7 Vernon Hills 34.7 Prairie View 32.0 Buffalo Grove 29.9 Wheeling 26.6 Prospect Heights UP Milwaukee Subdivision UP-NW to McHenry or Harvard to Ogilvie I-90 19.8 O'Hare Transfer ATS Blue / I-190 18.6 Rosemont I-294 17.4 Schiller Park 15.8 Belmont Avenue NCS to Union Station 15.5 MD-W to Elgin | to Union Station to IHB and BNSF Chicago Subdivision Des Plaines River Union Pacific 11.0 Forest Park Waukesha Subdivision Altenheim Subdivision Baltimore and Ohio Chicago Terminal Railroad

The Waukesha Subdivision or Waukesha Sub is a railway line owned and operated by the Canadian National Railway. It meets the Neenah Subdivision to the north in Fond du Lac, Wisconsin and runs south to Chicago, Illinois.

Construction of the line started in 1882 by the Wisconsin Central Railroad and was completed in 1886.^[1][2] The railroad was reorganized from bankruptcy in 1897 and became the Wisconsin Central Railway.

The Minneapolis, St. Paul and Sault Ste. Marie Railroad (the original Soo Line) gained control in 1901 and leased the WC in 1902. The Soo Line operated the WC as its Chicago Division. After the 1961 Soo Line-WC-DSS&A merger that created the Soo Line Railroad, the railroad reduced the number of its operating divisions from five to three; the Schiller Park to Fond du Lac segment became the Soo Line's First Subdivision of the Eastern Division.

After the Soo Line acquired the Chicago, Milwaukee, St. Paul and Pacific Railroad (Milwaukee Road) in the bankruptcy auction, the line, among others, was placed in the Lake States Transportation Division in an attempt to cut costs. After the failure of this cost-cutting exercise, the LSTD was sold to Wisconsin Central Ltd. in 1987, which was then sold to Canadian National in 2001.^[3]

The Wisconsin and Southern Railroad has trackage rights over the line from Slinger to Waukesha, and freight cars are interchanged between the two railroad companies in Ackerville.^[4][5] Metra, Chicago's commuter rail service provider, also operates on this line as its North Central Service route (between Chicago Union Station and Franklin Park, Illinois, NCS trains use the Milwaukee District West Line, but do not stop at any of its stations, with the exception of the River Grove station). In Forest Park, Illinois at Madison Street, the subdivision connects with the B&OCT (CSX)'s Altenheim Subdivision and continues into Chicago. Also, Soo Line passenger trains historically used this line at Forest Park to access the Baltimore & Ohio Railroad's Grand Central Station (Chicago).

One of the obstacles faced by southbound trains is Byron Hill, which was a helper district when the line was operated by the Soo Line. Canadian National double-tracked that part of the line shortly after acquiring it.