4. There's a haunted pet cemetery
Okay, so who knows if it's really haunted, but legend has it that the Presidio's pet cemetery used to be the final resting place for cavalry horses and military guard dogs in the 19th century. However, at some point in the 1950s, it became an unofficial place for military families to bury not just their dogs and cats, but also their parakeets, canaries, macaws, rabbits, hamsters, rats, lizards, goldfish, and mice.
In 1994, when the Presidio was being converted to a national park, Rep. John J. Duncan, Jr. (R) of Tennessee called it the country's "smallest and most expensive national park" as a way to draw attention to the federal deficit. To drive his point home, he sent photos of the pet cemetery to his supporters asking, "Is This Your Vision of a National Park?". All we have to say to John is: yup, it sure is.