Anatomic and clinical studies show many variants of the superficial peroneal nerve (SPN) course and branching within the compartments and at the suprafascial layer. The anatomy of the transition zone from the compartment to the subcutaneous layer has been occasionally described in the literature, mainly in studies reporting the intraseptal SPN variant in 6.6% to 13.6% of patients affected by the SPN entrapment syndrome.Despite the little evidence available, the knowledge of the transition zone is relevant to avoid iatrogenic lesions to the SPN during fasciotomy, open approaches to the leg and ankle, and SPN decompression.Our anatomic study aimed to describe the SPN transition site and to evaluate the occurrence of a peroneal tunnel and of an intraseptal SPN variant.