Onalaska, WI

ZIP code 54650 serves Sparta in western Wisconsin, the county seat of Monroe County. Notable landmarks include the Monroe County Courthouse and the Deke Slayton Memorial Space and Bicycle Museum, which honors the Sparta-born astronaut and the region’s cycling history. Sparta is also the western trailhead of the Elroy-Sparta State Trail, a rail trail known for its tunnels and connections to other Wisconsin recreational trails.