I'm from Two Rivers, just a few miles north of Manitowoc. The waysides are beautiful in the summertime. They are right on the lake, as close as you can get. Even on the hottest days, it's always comfortably cool on the lakeshore. As it starts to warm up around here, we can count on 60 degree weather.
There are a handful of these rest areas along the way, as Paul said, with shade, restrooms, and tables. They're easy to find as the rest areas are nestled between Maritime Drive (a 4 lane road many take on their way to Door County) and Lake Michigan.
We can make this work!!!