AT 15 minutes past midnight on June 6 1944 began what was officially code-named Operation Overlord. But from that day on, the historic event became known simply as D-Day.

Three million men left for the shores of northern France aboard 7,000 ships and 11,000 aircraft – the biggest invasion force ever assembled – with the intention of destroying the Third Reich and ending the Second World War.

Preparations for the long-awaited second front in western Europe had depended upon intensive and meticulous military planning with more men, vessels, aircraft and equipment than had ever been seen before.

Troops began pouring into the south of England, more than one and a half million of them American, and no two counties played a more important role than Dorset and Hampshire.

Blandford housed the US Army 22nd General Hospital and US Army units. Nearby Langton House was HQ of 1st (US) Infantry Division.

Breamore House near Fordingbridge was used by Gen George Patton as his headquarters in the run up to D-Day.

Bournemouth was a “defence area” and all civilian visits were banned. Most hotels were relinquished for military use. Aircrew trained in dinghy survival in the Pier Approach baths. Anti-aircraft guns were sited on high buildings like Beales. King George VI reviewed airmen in the Pavilion.

Bovington, home of the Royal Tank Regiment, saw much training from the beginning of the war. To counter possible enemy landings from sea and air, mobile columns were set up to operate in a 45-mile radius of Bovington.

Christchurch aerodrome was a base for the Air Ministry Research Establishment’s special duties flight and USAF Thunderbolt. Camouflaged factories built planes and gliders and converted Spitfires into Seafires.

Hengistbury Head and Mudeford were armed with coastal defence artillery batteries.

In Hamworthy, the first Royal Marine commandos trained at amphibious warfare centre HMS Turtle. Bolson’s and Newman’s shipyards built landing craft around the clock (the largest number in Britain) and RAF Hamworthy was a seaplane base.

Holton Heath housed a Royal Navy cordite factory and West Moors a military petrol depot.

Hurn Aerodrome, then in Hampshire, saw radar trails and paratroop training and was a base for Typhoons, Mosquitoes and B-26 bombers. Tarrant Rushton and Hurn held key positions because they lay closer to the Nor-mandy drop zones than any other major airfields.

Lulworth Camp was an armoured fighting vehicle school and suffered several air raids. Enemy planes crashed at Kim-meridge, Winfrith Heath and Bindon Hill.

The New Forest saw more than 100,000 men under canvas and thousands of military vehicles parked on its quiet country roads. Airfields like Holmsley, Ibsley and Beaulieu enjoyed their own finest hour. Exbury House was renamed HMS Mastodon and used for the victualling, arming and training of landing craft crew. More than 1,000 personnel passed through the building, which later bore the names HMS King Alfred and HMS Hawke.

Poole was the embarkation point for tens of thousands of troops. GIs were billeted in homes, the US Coastguard had a base and the US army took over quays, yards and yacht clubs. More than 100 anti-aircraft guns protected the town.

Shaftesbury saw the establishment of a military hospital where the Guys Marsh young offenders institute is now.

RAF Sopley was a radar tracking centre. USAF Thunderbolts were based at nearby RAF Winkton.

St Leonards Hospital near Ferndown was set up to treat casualties from France. Radio contact with the French and Dutch resistance was maintained from a bunker under the St Leonards public house.

Studland Bay was the venue for practice beach landings, leading to a mock invasion in front of the King. Swanage beaches were mined and swathed in barbed wire. Hotels and homes became barracks and billets. The White Horse Inn was the US Red Cross centre and the Grosvenor Hotel hosted the King, Montgomery and other VIPs. The town suffered many air-raids.

Gliders from Tarrant Rushton carried the first Allied troops on D-Day to Pegasus Bridge. Night flights dropped supplies for the French Resistance and Special Operations Executive. Injured troops were flown back here for transfer to Blandford hospitals.

Woodland around Verwood hid troops and equipment, and sandpits at Stephens Castle were quarried to build Mulberry Harbours.

US troops were billeted at Wareham, Corfe Castle, Lytchett Minster and Upton.

Weymouth and Portland saw the biggest embarkation of men and equipment, primarily American. Nearly half a million men and 140,000 vehicles passed through these two ports. The lighthouse at Portland Bill was designated the official navigational port of departure for the aircraft carrying the paratroopers ahead of the airborne assault. Portland was described as the “biggest little port in the world” by the Americans. They were heading towards “Bloody Omaha” where the heaviest losses were suffered. Units of the 1st, 3rd, 9th and 15th Armies, along with a French armoured division, would pass through Weymouth en route for Normandy. Around 40,000 prisoners of war were brought into the area as the allies advanced through France but, remarkably, by the end of the summer, Weymouth began to return, albeit slowly, to being a holiday town.

Wimborne billeted British troops. Farrs House was an officers’ mess. Canford Bridge was an “immigration post” to keep civilians out of restricted Poole. A US field hospital was set up at King-ston Lacy Park.

Worth Matravers housed a radar experimental station which provided vital technical back up.

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