自古

zìgǔ
  1. (since) ancient times
  2. (from) time immemorial

CEDICT

Entry Composition

1 自 zì
  1. (bound form) self; oneself
  2. from; since
  3. naturally; as a matter of course
2 古 gǔ
  1. ancient
  2. old
  3. paleo-