North Park is located in northern Allegheny County in McCandless Township.
The Lakeshore Pavilion is located on Lake Shore Drive in between Walter Road and... Walter Road.
From McKnight Road, turn east onto Ingomar Road for one mile. Turn left onto Kummer Road, then almost immediately turn right onto Walter Road. Lake Shore Drive will split off to your right. Follow it around until you reach the pavilion. There is angle parking slightly south of the pavilion, in between the roadway itself and the bike path.
The Showcase Cinema North Park and Ride stop on the Port Authority's 12 bus comes closest on weekends, but it's still 2-3 miles away. Carpooling is probably a better option.