At the end of a 21-song set Sunday night to close out Outside Lands, Paul Simon brought out the great Bob Weir of the Grateful Dead — a friend he's known for 52 years.

Simon describes arriving in the Bay Area for the first time in 1967 to perform at the Monterey Pop Festival, and knocking on the door of the house where he'd be staying to have Bob Weir open the door. "And we've been friends ever since," Simon said. "But actually, this is our first duet." Simon brought Weir out on stage to join him in the Simon & Garfunkel classic "The Boxer," and the two made great music together.

Another angle, via Low Fat Music:

Simon, 77, has said that he has stopped touring, and his only shows going forward will be done for causes that he cares about. Proceeds from his appearance at Outside Lands went to San Francisco Parks Alliance and Friends of the Urban Forest.

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