A line previously existed from West Chicago to Elgin, with branches beyond to Freeport and to Crystal Lake and points beyond. This was the original line to Williams Bay, with passenger service eventually cut back to McHenry. Service was discontinued over this segment in the early 1930's, with service north of Crystal Lake instead operated via the Wisconsin Division main line.
Milepost locations are indicated, distance from Chicago via West Chicago.
East Dundee (47.6) - station was located on River St. between Railroad St. and Barrington Ave., on the east side of the track. The building still stands.
Carpentersville (48.4) - station was located west of the intersection of Washington St. and Wisconsin St., on the east side of the track.
Algonquin (52.9) - station was located on Railroad St. between Main St. and Jefferson St., on the east side of the track.
Crystal Lake (58.5)
Kane County (NE)
McHenry County (E)