From Escanaba to St. Ignace the route stays mostly on US 2. This highway is very busy with both recreational and commercial traffic, but generally has wide paved shoulders. In general, when US 2 is directly on Lake Michigan shore or well inland it is flat, but in between there are numerous climbs over coastal bluffs which provide spectacular views of the lake. The Mackinac Bridge between St. Ignace and Mackinaw City, which connects Michigan's Upper and Lower Peninsulas, is part of I-75, and bicycles are prohibited. Adventure Cycling recommends riding the ferry to Mackinac Island to cross the Straits of Mackinac. No motorized vehicles are permitted on the island, which is 80% state park, and 20% privately owned. The Manitowoc Alternate can be used as a shortcut between central Wisconsin and the lower Michigan peninsula. It shortens the route by 215 miles by using a ferry across Lake Michigan.
The alternate Manitowoc route goes near our place (Sherwood, WI) and my wife and I will use the route to Manitowoc as part of the Bike Travel Weekend this June 2018. The part I know is very good all over open farmland with low trafic and surface in decent condition. Sherwood has a grocery, a convenience store and a warm weather ice cream shop. Very nice bike area.