The Noquemanon Trail Network is Marquette's outdoor playground, a linked system of singletrack, ski routes, snowshoe paths, and trail-running loops around town and the surrounding woods. It is one reason Marquette punches above its weight as an Upper Peninsula base.
The network is split across several areas, so pick a trailhead rather than assuming there is one obvious entrance. In summer the draw is mountain biking and forest hiking; in winter the groomed Nordic and fat-bike routes keep the system alive when Lake Superior country is buried in snow.