ALLIES DISRUPT GERMAN DEFENSES IN FRANCE
London, England • June 1, 1944
In June 1942 members of the French Resistance provided British intelligence with a copy of the top-secret blueprint of portions of Adolf Hitler’s Atlantic Wall—part of the defenses against the anticipated Allied invasion of Western Europe. The map had been spirited from the office of the German public works bureau that was building the coastal defenses, and it revealed the strong and the weak points along the entire Northwestern French coast of Normandy, from Cherbourg in the west almost to Le Havre in the east.
The French Resistance continued to pass the Allies detailed information about the Normandy invasion area (gun emplacements and caliber, real and fake minefields, gaps in German flak defenses, etc.) right up to D-Day—information provided in part by some of the thousands of French laborers and Italian POWs Field Marshal Erwin Rommel (he of Afrika Korps fame) was using to build stronger coastal defenses, plant millions of landmines (6 million in Northern France alone), flood large areas behind the flat beaches to drown Allied paratroopers, and drive long poles called “Rommel’s asparagus” into open fields to thwart the safe landing of Allied troop gliders.
In advance of Operation Overlord, the codename for the June 1944 Normandy landings, Allied aircraft began pounding synthetic oil plants in Germany, which reduced the Luftwaffe’s fuel supply by nearly 70 percent between April and this date, June 1, 1944. Allied intelligence estimated that the enemy could lay hands on two million freight cars to move troops and supplies to the invasion front. So to prevent the Germans from deploying, reinforcing, and resupplying their beachhead defenders, Allied aircraft heavily bombed and cratered French and Belgian highways, tunnels, river crossings, and railroad yards. Heavy were the civilian casualties caused by these air raids, as well as from sabotage by Resistance fighters on the ground, particularly by Résistance Fer, the organization of French railwaymen: over 12,000 people lost their lives. (The Germans were quick with reprisals, executing several hundred cheminots, as the French railwaymen were known, and deporting another 3,000 to German camps.) But 80 classification/marshalling yards and 1,500 locomotives were put out of commission, along with miles of railroad tracks (950 cuts), water pumps in the railway yards, numerous bridges, tunnels, and communication lines, heavy lifting cranes, 36 airfields, 45 gun batteries, and 41 radar installations that the enemy would desperately need to throw back the invaders.
When the first invasion ships set sail from England on June 4, 1944, and troops finally set foot on Festung Europa, Fortress Europe, two days later, the Allies had neutralized the Luftwaffe over France (the Germans had less than 160 serviceable aircraft) and degraded the enemy’s ability to move on land.
German Atlantic Wall Defenses on the Eve of Operation Overlord
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Above: Map of the 1,668-mile-long Atlantic Wall shown in green. The wall hugged the coastline from Norway to Spain in varying degrees and was most elaborate facing the English Channel. It consisted of an extensive system of coastal fortifications built between 1942 and 1944 as a defense against an anticipated Allied invasion of the continent. In France the wall comprised a string of reinforced concrete casemates housing heavy-caliber guns, bunkers housing smaller artillery (100‑210mm guns), and pillboxes along the beaches or sometimes slightly inland, as well as mines and antitank obstacles planted on the beaches or in waters just off shore. A major engineering feat for its time, the Atlantic Wall for most of its length was nevertheless a porous barrier because Germany and the occupied states lacked the resources to seal it completely. Along one 55‑mile beachfront in Normandy, strongpoints were 650 to 1,100 yards apart; some undefended sections were as much as three times that wide.
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Left: In November 1943 Field Marshal Erwin Rommel took command of German Army Group B in occupied France. He also took control of the Atlantic Wall defenses on the French coast facing England. In this photo from April 1944, Rommel and his officers can be seen inspecting an installation of obstruction beams (Hemmbalken). Some were topped with Teller (German for “plate”) mines, detonating when Allied landing craft passed over them. The Allies modified their original plans to land troops at high tide, closer to the shore, in favor of landing at a rising tide when the obstructions and mines could be seen and avoided. The disadvantage with the revised plan was that it increased the length of beach to be crossed.
Right: In 1943 German troops had begun using hydraulic pressure hoses to assist in planting high wooden poles (Hochpfaehlen) in beach sand as obstacles to landing craft. In February 1944, on a tour of Channel beaches in Pas-de-Calais opposite England, Rommel ordered the technique used to place wooden beams, hedgehogs made out of steel girders, and other antilanding obstructions along Normandy’s beaches. Nearly 11,000 were installed on the coastline where the Allies would land.
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Left: Rommel sent his subordinate commanders sketches like the one depicted here for laying out wooden log and wire defenses against airborne assaults. Barbed wire and tripwires were to be strung between the poles. The complete system of wooden poles and interconnecting wires was called Luftlandehindernis.
Right: “Rommel’s asparagus” (Rommelspargel) refers specifically to wooden poles used against aerial invasion. Wooden tree trunks and logs set in French fields and meadows in 1944 were intended to cause damage to military gliders (e.g., by tearing off their wings) and to kill or injure glider infantry in an uncontrolled landing. Though more than a million of these poles were erected, their effect on the invasion of Normandy was inconsequential.