On May 1, 1959 — Dick Stuart’s 9th-inning, two-out, two-run bomb makes it close but the last-place Cardinals hold on, ending their three-game skid with a 7 – 6 squeaker over Pittsburgh. Stuart’s near-500-footer, however, provides fodder for rooters and writers alike. Les Biederman reports: “Fans left Forbes Field buzzing about the tape-measure home run Stuart hit over the scoreboard in the 9th. Jim Brosnan had two strikes and no balls on Stuart when he fed him a curve. Stuart flicked his wrists and the ball was still zooming as it rose well over 100 feet above the height of the wall and landed somewhere in the parking lot far into Schenley Park. ‘It was the longest I’ve ever seen hit at Forbes Field,’ coach Howie Pollet of the Cards offered and manager Solly Hemus and coach Harry Walker both agreed.”

Source
Baseball Reference May 1