a long time ago; long before now
「前々」 has another reading with different meanings.
前々から気になっていた店に入ってみた。
I went into a shop I had been curious about for a while.
前々よりこの問題は予測できた。
This problem could have been foreseen well in advance.
前々から準備していたのに当日は天候に恵まれなかった。
Although I had been preparing well in advance, the weather was not on our side on the day.