It is believed that somen production became active because the area was blessed with good ingredients such as high-quality wheat from Harima, clear flow of the Ibo River, and salt from Ako.
播磨地方の良質の小麦、揖保川の清流、赤穂の塩など原料に恵まれていたことから素麺作りが盛んになったと云われる。