The engineers of the Atlantic wall went with a different design

A good what if on the Atlantic Wall.
Most of what I wanted to say have already been posted so I'll just add what I can.
When I read this what if, the first thing that came to my mind was the saying "He who defends everything, defends nothing."
A Maginot-type line on the beaches would make the Allied job of invading harder, not impossible. As I've said in a post in another thread, war can be seen as a series of "action and reaction" with the one who fails to react or act properly falling on the wayside.
Applying this idea to the what if posed here, I would say that the Allies would develop new plans in response to what the Germans are doing.
Since the Germans didn't really have a reliable intelligence network, they would be prepared to deal with what they think is the Allied capability.
However, the Allies would undoubtedly develop new plans and even methods to deal with the developing German defense.
I'd say that this would mean that the Allies would look at the Med, probably Italy, as their likely invasion point. They'd probably still retain Patton's ghost army in England to make the Germans think that the Allies are still poised over the English Channel.
This gives rise to a question of mine. If France is so heavily defended, could the Allies stage their invasion through Greece?
German reinforcements to meet an Allied invasion there would be delayed by Yugoslavian partisans (which were historically fighting each other as often as they were fighting the Germans). Another advantage of such an invasion is that it could also poise as a direct threat to Rumania, which is a major source of Germany's fuel.
This might be far fetched but I'm willing to consider that an invasion of Greece is preferable to the heavy losses that the Allies would likely suffer in TA's heavily defended Maginot-like Atlantic Wall.
As for those who push for the use of Airborne units, I would have to say that this would invite a massacre for the Allies. Airborne units need to link up with the main force within days of the drop. If the main force is delayed by TA's Atlantic Wall design, the Airborne units would wither in the vine.

 

If I were the Allies facing a much more heavily defended Atlantic Wall in France I too would look elsewhere for a good invasion site.

Now, as the Allies I would also know that the Germans could not seriously challenge, let alone stop, the naval portion of the invasion. I can move a fleet virtually anywhere with impunity against Germany by early 1944. I would also know that Hitler tries to defend everything and is prone to panicked decisons with regard to surprises and unexpected developments. So, I would propose a "reverse Anzio" with the initial assault launched from the US where the Germans literally would never see it coming.

So, the question now is do I titilate readers by ending the post and adding the conclusion now or later? Later tonight I think......

 

An invasion into Brittany.

That will end run the Germans.

 

No, invasion into Germany itself in the Helgoland Bight. The Allies land two divisions along with a parachute unit in daylight on the beaches followed by two more divisions. These dig in and await the inevidable German knee jerk response. As with the North Africa invasion the initial divisions come from the US by convoy along with the entire Atlantic Fleet. Air cover is provided by a combination of escort carrier and long range ground fighter from England until airfields are up and running (D + 5 to 10).
After that, the Germans are seriously hit. They find themselves in another Anzio they can't win but they can't give up.

As soon as the Germans pull everything but the kitchen sink into crushing this landing the Allies invade cross channel into the now empty defenses of the Atlantic Wall. The first invasion just digs in and holds its ground as the Germans find themselves now faced with a mobile war in France and nothing there to fight it. They lose big time and end up by September 1944 on their own borders with the Allies crossing the Rhine.

 

I agree that landing elsewhere would draw the German mobile forces away from the Atlantic Wall but most probably those stationed to man the fixed defenses would stay.
Your subsequent cross-Channel landing would then be facing a German defense that has a thick crust but would be hollow underneath.

 

There are certainly a lot of good points mentioned already. For the sake of a good "what if", I believe that you have to concede to the idea that Germany did have the material and the resources to fortify the Atlantic wall. Otherwise there would be no point in pondering the possibilities. One cheap and very possible alternative would be just a little landscaping. Make sure that all cliffs were near vertical and rig them to blow when the rangers began their climb. Digging a deep trench at the base of the cliffs ( say 7 meters wide x 5 meters deep ) would surely be another pain in the butt to overcome and would definately slow the advance of tanks. I know the naval fire would have destroyed some of the cliffs but that would be a good spot for concentrated machine gun fire. I would have used the entire coastline for one huge dump. I would have beached every obsolete ship, boat, and whatever (cars, planes, concrete blocks, you name it and I would have dumped it there). Throw in some barbwire and maybe some more barbwire and if possible more barbwire. It would have been an ugly site no doubt but I believe it would have been effective. I personally don't believe an all airborne D Day would work without tanks and artillery. But then again, "what if".

 

The seawalls on the beaches were reinforced as tank or vehical barriers. They required engineering efforts like bulldozers, facines, explosives... to allow the tanks and other vehicals to pass

The entire beachs were used as machinegun, mortar, & artillery concentration areas. Obstacles to fire and observation were removed.

Everything that could be had was used to block the ports. This was a good investment for the Germans as it typically took weeks, months in some cases for the port salvage units to clear the harbors. This upset the logistics plans and was the largest contributor the lack of fuel and ammunition in September.

 

Actually, according to US Naval salvage experts the Germans did a sloppy and amaturish job of port destruction just about everywhere they had to do this. The men assigned did not understand naval salvage and usually failed to sink block ships, demolish equipment and facilities in the most efficent manner. This made port clearance much easier for the Allies.

 

To a certain extent, you have a point, T.A. but still even with the amatuerish manner the Germans did in port destruction, it was still enough to hamper the allies as pointed out by Carl. We are all fortunate that the Germans were not efficient as they should have been.
I've been reviewing what you've said about Anzio and your proposed landing in Helgoland Bight offers some intriguing possibilities for Allied exploitation.
However, I think there's a weak spot on your proposal, T.A. It seems that your landing's success depends on a knee jerk reaction from Hitler. Don't get me wrong, your plan is sound but I prefer to overestimate the capabilities of a potential opponent. That way, I leave a little insurance and leeway to handle surprises.
One thing sure, your proposed landing is a better idea than mine, which was to make a landing on Greece.

 

Everything I`ve read describes how it took weeks even months to restore the ports to partial capacity. ie: Ellseberg `The Far Shore` summarizes his inspection of Cherbourg the week it was captured. ( Ellseberg was a USN salvage officer who had been deeply involved in restoring Naples port.) `Day of Battle` by Atchinson has a acessable description of the damage to the port at Naples. The US Army Green Book `Logistical Support of the Armies` has several chapters in Volume I decribing the expectations of the Alied logistics planners, and the reality after the ports were captured. The numbers for supply delivered through the ports vs planned are enlightening.

Amatures or not, the Gemans filled the harbors with sunken ships and boats, mines, rail cars and automobiles. The docks cratered with explosives, rails broken up, and buildings burned or mined.

 

According to Captain C A Bartholomew, USN in Mud, Muscle, and Miracles, Marine Salvage in the United States Navy

Naples harbor was opened in 14 days with eight berths and there were thirty berths in two and a half months (more than existed within the harbor pre-war).
At Cherbourg, it took EOD crews a month to clear the port of mines before salvage could begin. The harbor was partially opened within thrity days after that.

 

For the Normandy/ French campaign I suppose the Germans held onto so many ports until the end of the war that whether the Germans did a bad job destroying the ports did not matter??! Or did it?

 

Which in both cases was longer than the Allied logistics planners expected or allowed for. And, in both cases severely restricted the supply the Allied armys during those months. And, still does not negate my remark that the Germans sank every hull, hulk, and scow available in the harbors.

Moving closer to the core of the topic I`ve skimmed back through a few books & other sources, and am reminded that the Atlantic wall was not so far removed from the `Maginot Line` in size and scope of the fortifications. I dont have time to assemble statistics, but if one uses the German definition of the Atlantic Wall then it may exceed the French item in terms of concrete poured and cannon installed.

 

Didn't the Germans also sink one ship ontop of another to slow down the salvager's work at Cherbourg?

 

No. In fact, the salvagers noted this in particular. One commentary was about a old French submarine rescue craft sunk in the harbor entry. As this ship was in such bad condition the salvage consisted of cutting it up in chunks and lifting it out of the way. Had the Germans piled on another half dozen or more ships on top of it it might have taken months to open the harbor.

The Germans did do this at Ferryville in Africa. There they piled 28 ships into the channel leading to Lake Bizerte. But, even there they didn't pile them up deliberately. The current in the channel did the work. The other mistake was not filling the ships with maximum ballast (sand and or cement) to reduce their bouyancy. The USN took the expedient of cutting up the wrecks and then pounding them into the channel bottom using over 100 tons of explosives.

 

Now that's very real literal definition of "Flatten them!"