The transversalis fascia is a layer in the make-up of the posterior inguinal wall. It is the deepest, thinnest, and least important layer in terms of the prevention of herniation. It is a segment of the wider endoabdominal fascia. The true posterior wall of the inguinal canal is formed, in varying degrees, by the muscles or aponeuroses of the internal oblique and transversus abdominis. Plainly, Daedalus was not needed to show surgeons and anatomists how to make a labyrinth out of a rabbit hole!