Robert Plant and his wife were in a car crash while on holiday in Greece which broke Plant's ankle. Instead of touring the US, Plant and Jimmy Page wrote material for Presence
, then recorded it at Musicland Studios in Munich, Germany with Plant in a wheelchair. Plant got so excited while recording this that he fell and re-injured his ankle, similarly to the song's namesake, Achilles. The title was both an acknowledgment of Plant's broken ankle as well as to the mystic location in the Atlas Mountains of Morocco which inspired the lyrics.
Nick - Warwick, RI