Schaller Park is a riverfront park in Watertown. It was slightly hard to find unless you know it's there. There is no parking to speak of, but it is definitely peaceful. It reminded me of a giant, fancy backyard.
The park has a climber and swings. There is also a lot of waterfront (read: goose poop). We had a nice little snack picnic, and then about a half hour of play was enough.
1200 Riverview Lane ~ Watertown, WI