For quite an unusual encounter, head towards the western end of the park - you'll find a pasture with a herd of American bisons there. Walk along the right side of the enclosure for the best chance of spotting these huge animals.
Official Website https://goldengatepark.com/buffalo-paddock.html
Address San Francisco 94122, United States
Coordinates 37°46'11.084" N -122°29'54.201" E