High Quality Content by WIKIPEDIA articles! Operation Tracer was a highly classified, World War II military operation based in Gibraltar, then a British colony and military base. The impetus for the plan was the 1940 scheme by Germany to capture Gibraltar, code-named Operation Felix. Operation Tracer was the brainchild of Rear Admiral John Henry Godfrey, the Director of the Naval Intelligence Division of the British Admiralty. In 1941, he decided to establish a covert observation post at Gibraltar that would remain operational even if Gibraltar fell to the enemy. From the facility, the movements of enemy vessels would be reported back to the United Kingdom. Godfrey requested the assistance of several distinguished consultants to bring the plan to fruition. The plan was so top secret that Godfrey held meetings with his consultants at his private residence rather than at Whitehall. The decision was made to construct the facility using the existing tunnel system for Lord Airey`s Shelter, the underground military shelter just north of Lord Airey`s Battery. The artillery battery was located at the upper ridge of the Rock of Gibraltar, near the southern end of what is now the Upper Rock Nature Reserve.