Door County is the thumb of Wisconsin, a limestone peninsula that sticks into Lake Michigan like a hitchhiker's hand, and Sturgeon Bay is the town where you come in. It is the only real city on the peninsula, with about nine thousand people, a shipyard, a downtown that climbs a hill from the water, and a ship canal that makes the northern half of Door County, in effect, an island. The canal was cut in 1881 to connect Green Bay with Lake Michigan, saving ships the long, dangerous trip around the tip, and it is crossed by a steel bridge that lifts to let freighters through. If you are held up there, watch for the long, low ships sliding past at head height.
The shipyards have built vessels here for more than a century, from wooden schooners to Great Lakes freighters and, in more recent years, large naval ships. That industrial skyline is part of the town's character, set beside the restaurants and galleries that serve visitors. The surrounding orchards are cherry and apple, and Door County is famous for its cherries, in pies and in dried form. You should also try a fish boil, a local ritual in which whitefish and potatoes are cooked in a kettle over a wood fire, with a dramatic boil-over of salty froth. It is as much theatre as dinner.
Sturgeon Bay is practical for a rider. Fuel is easy, groceries and coffee are plentiful, and accommodation is spread across town. From here, state highways run north along either shore, through pretty towns and past farm stands. The riding is gentle rather than technical: gentle bends, long views to the water, and a lot of cars in summer and autumn. Weekends in July and October, when the leaves turn, are slow and crowded, so aim for a weekday morning. Winds off the lake can be strong, and fog sometimes rolls in during spring.
The peninsula's limestone bedrock is part of the Niagara Escarpment, the same ridge that makes the falls, and it shows in the white cliffs on the Green Bay side and the cobbled beaches on the lake side. Lighthouses are scattered along the shore.
Fill the tank, eat well, and then turn north. The best of the peninsula is still ahead of you.