千せん古こ万ばん古こ

noun

remote antiquity; ancient times; the remote past

A yojijukugo (four-character idiom) used in formal or literary contexts to refer to the very distant past, often with a sense of timelessness or eternity.

• この伝でん統とうは千せん古こ万ばん古この昔むかしから受うけ継つがれてきた。

  This tradition has been passed down since remote antiquity.