Frank Youell Field was one of the original stadiums they used.
They did play at Frank Youell Field from 1962-1965. The first year
of their franchise, 1960, they played in Kezar Stadium. The next
year (1961) they moved to Candlestick Park. After the three years
at Youell Field, they moved to McAfee Stadium in 1966 and have
played there ever since, except of course the 13 years (1982-1994)
they played in the L.A. Memorial Coliseum.