On December 6, 1969 the Rolling Stones hosted a free concert at the Altamont Speedway in Northern California. Jefferson Airplane performed at the concert, where, during the Stones' set, 19-year-old Meredith Hunter was murdered by a member of the Hells Angels.
The Altamont Free Concert is considered one of a handful of events that signaled the end of the peace and love era. Evidence of Hunter's murder can be found in the documentary film Gimme Shelter (1970). At bottom is an excerpt -- Jefferson Airplane's version of Fred Neil's "The Other Side of This Life" (1965).