Dolores Park was a Cemetary
Until 1906, San Francisco burials occured in the city limits. Now, death is no longer permitted within the city limits because of space considerations. This led to the expansion of the cemetaries in Colma, the cemetery town, just south of San Francisco. Many of the City's parks such as Dolores Park were once cemetaries. In fact, Dolores Park, once a Jewish cemetery, was sold to San Francisco in 1905 for nearly $300,000! In 2001 dollars, that is about 3.8 Million dollars!
This was good timing for the 1906 Earthquake --- Dolores Park now public land -- was put to good use. The city was in ruin and people built emergency shelters on top of the sacred earth of the 'Mission Cemetary'. Here is a photo of the temporary barraks built over gravestones.
The exact number of the dead people buried within The City boundaries is uncalculable due to the massive amounts of paperwork destroyed in the Great Earthquake of April 18, 1906. Calculations today are also difficult to extrapolate, here is a clip from a San Francisco Newspaper article:
"Time, weather and vandals asumed control, weeds choked the gravel paths, over-ran the graves. Tombstones fell. Ornuments, such as brooding angels became bedraggled -- wings, arms, and legs missing."
People are trying to cover up these facts.
"Colette Brumfield, a City College student, spoke of time when she experienced a strange presence at Dolores Park, in San Francisco’s Mission district. She was sitting on a bench with her boyfriend when she heard a clapping sound behind her as if it was coming up from the tree. Looking at her boyfriend she knew he felt the same strange presence she did. It was four in the afternoon, and her boyfriend had said, “Let’s get out of here before it gets dark!” Suddenly things did get dark, they left immediately hearing someone laugh right behind them. “There were only two people in the park mind you, me and my boyfriend,” said Brumfield." -- more info
jblcktt has more info