The Rock River runs through downtown Janesville, a city that maintains links to its richly varied past through ten historic districts. Nearly twenty percent of all Wisconsin buildings listed on the National Register of Historic Places can be found in Janesville. These include the Lincoln-Tallman Restorations on the west bank of the river, with a mansion that hosted a visit from Abraham Lincoln in 1859. Today, Janesville is home to the only remaining automobile production factory in the state, a General Motors assembly plant for their popular Suburban, Tahoe and Yukon SUV lines. Five miles to the northeast, visit the Milton House Museum. This 1844 stagecoach inn was once a station on the Underground Railroad, complete with a secret tunnel.