In a newspaper article (in Concord Monitor of 1977) I read that Simon and Garfunkel gave a free concert in Concord. Here’s a bit of that history.
The free concert was organised by The Timothy and Abigail B. Walker Lecture Fund with the thought
“that the popular music of today is valid music and should be heard“.
The concert was initially planned at the City Auditorium. The distribution of free tickets started in January. The requests for tickects must have been huge, so the concert was shifted to the Capitol Theatre which could house 1400 people. Not enough to house everybody it seemed.
Here’s the review by Hank Nichols in the Concord Monitor of February 20, 1967:
and a letter to the newspaper from a reader:
Paul Simon - 'Time it was...it was' 