Long before reunion tours became a natural part of being in a rock group, Simon & Garfunkel did what nobody thought they would do again. On Sept. 19, 1981, the duo reunited for a free concert in New York City's Central Park.

Despite being celebrated for their beautiful harmonies, by the time of 1969's Bridge Over Troubled WaterPaul Simon and Art Garfunkel could barely stand the sight of each other and called it quits the next year. However, they recorded a few songs together, Simon's "My Little Town" and a cover of Sam Cooke's "Wonderful World" with their friend James Taylor, but remained broken up.

But when New York City asked them to reunite to raise funds to renovate the park, they decided to bury the hatchet and help their hometown.

An estimated 500,000 people crammed into the park's Great Lawn for the event, which was filmed for HBO and recorded for a live album (the source of the revenue raised). On a stage designed to look like a New York City rooftop, Mayor Ed Koch introduced the pair, who then launched into "Mrs. Robinson" and 19 other songs, which included a handful of Simon's solo hits and one new number from each.

Despite the years and acrimony, they sounded as if they had never broken up. But there was one glitch. The performance of Simon's new song, 'The Late Great Johnny Ace,' was interrupted when a fan ran onstage after Simon sung a lyric about the killing of John Lennon, which had occurred nine months prior only a few blocks away from the site of the concert.

Bolstered by the success of the concert, Simon and Garfunkel embarked on a world tour that, predictably, ended badly. They toured again in 2003 and 2004, and sang at the Rock and Roll Hall of Fame 25th Anniversary concert, but as recently as May 2012, Simon said that he would not record with Garfunkel again.

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This Day in Rock History: September 19

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