On Kettle Moraine Drive, 2.5 miles north of State Highway 67, the Greenbush Recreation Area, located in the Kettle Moraine State Forest-Northern Unit, has two trail systems: four loops of challenging mountain bike trails totaling nine miles, interwoven with five loops of hiking trails totaling 13.5 miles. Hikers and off-road mountain bikers share this multiple-use trail system in season. For safety reasons, these trails are use-specific: hiking is not allowed on the bike trails and biking is not allowed on the hiking trails. In winter the hiking trails are machine-groomed for cross-country skiing. Pets and hiking are not allowed on the ski trails. The 1.2-mile Brown Loop at Greenbush is lighted for night skiing. The bike trails are excellent for winter hiking and snowshoeing. A heated picnic shelter, picnic tables, grill, drinking water, and vault toilets are near the trail head. There is also access to the Ice Age Trail. A state trail pass is required for all bike riders and skiers age 16 and over.