'Operation Neptune' was the codename for the naval component of the invasion of France in June 1944. The complete invasion codename was 'Operation Overlord', and 'Neptune' was therefore phase one of a much bigger plan. Nevertheless, the task of safely landing 160,000 men with all of the supporting equipment was an operation on an unprecedented scale. The operation, planned by a team under Lieutenant-General Frederick Morgan, was the largest amphibious invasion in world history and was executed by land, sea, and air elements under direct British command with over 160,000 troops landing on 6 June 1944. Of these, 73,000 were American troops, 61,715 British and 21,400 Canadian. To achieve the successful landings, 195,700 Allied naval and merchant navy personnel in over 5,000 ships were involved. The invasion required the transport of soldiers and material from England by troop-laden aircraft and ships, the assault landings, air support, naval interdiction of the English Channel and naval fire-support. The landings took place along a 50-mile stretch of the Normandy coast divided into five sectors: Utah, Omaha, Gold, Juno, and Sword. The planning required for such a mammoth undertaking was vast, and all to be maintained under the strictest secrecy. The fact that the Germans were caught by surprise is incredible, and a great debt of gratitude is owed to the men and women who worked so hard to bring off the greatest sea-borne invasion in history. This book, written only one year after the invasion by a senior British naval officer who was closely involved, provides the detail behind the conception, planning and successful execution of 'Neptune'.