The Badger State Trail is a 40-mile (64 km) rail trail in south central Wisconsin. The trail leads from the Wisconsin – Illinois state line to Madison passing through, from south to north, Monroe, Monticello, Belleville and Fitchburg. Near Monticello, the trail passes through the 1,200-foot (370 m) long, unlit Stewart Tunnel constructed in 1887. The trail was officially opened July 8, 2007.
Feasibility studies for the trail began in December 1976. Approval for the trail came in 1997. Some objections were raised in 1999 when both the Green County Board and the South Central Wisconsin Rail Transit Commission passed votes for the rail trail conversion. In 2000, the state Natural Resources Board purchased the right-of-way to develop the trail. Portions of the trail were opened for winter activities.
The trail was officially opened with a ribbon cutting ceremony in Belleville on July 8, 2007. Although the 6-mile long (9.7 km) section through Fitchburg wouldn’t be paved on the trail’s opening, in its first year of use as a recreational trail, the Wisconsin Department of Natural Resources estimated that, despite a temporary closure in August due to flooding, it was used by 31,000 people between July 1 and December 31, 2007, with 6,000 snowmobilers in December.
State and local representatives approved a spending measure to pave the northern section in September 2008. Finally on November 18, 2009, the Building Commission unanimously approved funding to complete the section in Fitchburg, allowing $497,000 to be borrowed in stewardship. In April 2010, the city of Fitchburg accepted bids to pave the trail and repair bridges and level crossings within the city.
In 2014, the northern end of the trail, where it intersects with both the South West Bike Path and the Cannonball Trail, was rebuilt to make the first bicycle roundabout in the Madison area.