It happened Sunday just after 5 p.m. in an area known as Sunset Cliffs.
Anna Bachman, 25, was taking pictures with her sister on one of those cliffs. Police say she backed up too far, lost her balance and fell about 40 feet onto the rocks below. She was killed instantly.
"There were quite a few other people who actually saw this. There were two nurses who were here that hustled down there really quick and tried to do CPR, as well as, I believe, a couple surfers that were in the water as well," a witness said.
Bachman was in San Diego to visit her sister. Her family members were notified and were traveling to San Diego Monday.