Mine are more recent...

When the concentration camps were liberated at the end of World War II, V-E Day and V-J Day
The American civil rights movement - Dr. King's speech at the March on Washington in 1963
President Kennedy's presidency and assassination (because everyone over a certain age can remember Camelot and exactly where they were on the day he was murdered)
The Monterey Pop Festival and Woodstock
The Beatles concert at Comiskey Park, Chicago in August of 1965 (I was born in September 1966)