Grindstone is a short drive down M25 from Port Austin – Follow M25 (Grindstone Road)and look for signs on your left (North)
Here is the old city, maintained, uninhabited and frozen in time.
Ice Cream Wars
Of course you have to stop and have an ice cream –
William eating a “small” Ice Cream.
Excerpt from the Thumbwind
It isn’t often that two shop’s offering the same fare open in a small town at the same time. But that is what is happening in Grindstone City. The Grindstone General Store is one of the oldest 
proprietorship’s in the Thumb. Its well known for its huge ice cream cones served up for kids of all ages. The store also offers items produced by local artists. What is less known is a relative new comer; Rybak’s Ice Cream and Candy Shop just down the street operating in a historic building, built by Aaron Peer in 1881. Rybak’s offers high end ice cream, homemade candy and assorted gifts from local artists.The shop once 
headquartered the Grindstone operations which the town is famous. The building has been beautifully restored.
A Great Lakes shipper, Captain Aaron Peer, sought shelter in the area’s natural harbor in 1834. As his crew explored the dense forest and rocky beach for shelter and firewood, the men came across huge flat rocks lying about the shore and forests. Taking samples south to Detroit, they found the stone (part of the Marshall Sandstone Formation) to 
be impeccably suited for paving streets, replacing Ohio flagstone as the preferred medium. Within a couple years, Captain Peer and his crew took advantage of the stone to sharpen their tools, and began shaping them into grindstones shortly thereafter. A small port grew here as industry took hold in the forest.
In 1836, Peer purchased 400 acres of land to establish a grindstone 
quarrying and manufacturing operation. The outcropping of Marshall Sandstone that Peer discovered was an abrasive stone with a very fine grit unique to Grindstone City and perfect for grindstones, scythe stones and hones. Worldwide demand soon earned the town the nickname of Grindstone Capital of the World.
The town became largely a company-built town, with homes, a grist mill, wharfs, and a booming industry with two quarries. A salt mining operation produced 125 barrels of salt each day during the 1870s, and the first railroad built into Grindstone City.
So next time you get a taste for ice cream, or are sick of Cheeseburgers in Caseville make the effort to get to Grindstone City. The choices are awesome.