I really enjoy Schenley Park. There are several well-built trails running throughout the park. They were created by the WPA back in 1939. The pond down below the bridge is not exactly something I would swim in, but I have seen people fish from it. The ice rink and ball fields at the Schenley oval are not fancy, but very accessible. In the winter many of the trails are cleared of snow, though it does get very icy.
The Schenley Park Visitor's Center - another WPA project - also offers free wireless internet, tasty baked goods, and coffee. There is outdoor seating around back.
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