Operation Marathon in World War II helped allied airmen who had been shot down or crash-landed in Nazi-occupied Europe evade capture by the Germans. The British intelligence organization, MI9, created the operation to gather downed airmen into isolated forest camps where they would await their rescue by allied military forces advancing after the Normandy Invasion of June 6, 1944. The Comet Line, a Belgian/French escape line, operated the forest camps with financial and logistical help from MI9.