The two men, and in particular Milk, have since been hailed as martyrs. Milk was the city's first openly gay elected representative, and one of the first LGBT leaders nationwide.
The men "died protecting our basic human rights," said Anne Kronenberg, Milk's former campaign manager and a co-founder of the Harvey Milk Foundation.
The two politicians were in their offices when they were hunted down and killed by former Supervisor Dan White. White entered City Hall through a window on the morning of Nov. 27, 1978. He shot Moscone four times in his office in Room 200, reloaded his revolver, then crossed the hall to shoot Milk five times in the supervisor's office.
That night, a spontaneous march broke out. Tuesday's march reflects that event.