Oku no Hosomichi chronicled Basho's journey up to his arrival in Ogaki around October 4, 1689 (when he composed the haiku that says, 'Like a clam ripped from its shell, autumn is deepening now.'
奥の細道では、旧暦8月21日頃大垣に到着するまでが書かれている（蛤のふたみにわかれ行秋ぞ）。