Whitefish Dunes State Park is on the Lake Michigan side of the Door County peninsula. We were there for hiking but there's also a dog beach. It's close to Cave Point County Park where THE views are.
We did the Red hike at Whitefish Dunes. It goes through forest on the way out, with a couple of cut-throughs to the beach, followed by a trip up Old Baldy — that was worth the trip for the views over the park and the lake — then back through more open dunes away from the shore. It was a little confusing figuring out if we were still on the right trail, but we found the parking lot in the end!
The second half of the hike featured wildflowers, open grass areas, and lots of grasshoppers.