Ping Tom stretches along the Chicago River and offers dramatic, bridge-strewn views of the skyline. Rent a kayak from the boathouse, or bring a picnic to eat under the willow trees. In summer, the Chicago Water Taxi (www.chicagowatertaxi.com) runs a groovy boat to/from Michigan Ave (the dock is on the bridge's northwest side, by the Wrigley Building). It costs $5 one way ($6 on weekends).
The park's entrance is a bit tricky to find. Take either W 19th St or S Wells St to where they meet, and you'll see a small park sign pointing the way in toward the railroad overpass.