The Brewery Hill Park is a great jumping off point to pick up a number of nice trails that meander through Whitewater. Located in the park is the Whitewater Rotary Skate Park, with enough ramps and walls to warm the heart of any skateboarder. Follow the trail onward through a nicely wooded area, over streams to a crossroads. There you can find links to further trails in the region, including Kettle Moraine, Lima Valley and the Ice Age Trail.
Here is an excellent trail site with these trails and thousands of others across the US!