Fans sit atop a painted bus at the Woodstock Music Festival in Bethel, N.Y., in August 1969.

Fans sit atop a painted bus at the Woodstock Music Festival  in Bethel, N.Y., in August 1969.

Fans sit atop a painted bus at the Woodstock Music Festival in Bethel, N.Y., in August 1969.

Fans sit atop a painted bus at the Woodstock Music Festival  in Bethel, N.Y., in August 1969.