Exploring the R612 Bunker on Utah Beach

80 years after the events of D-Day, and Utah Beach is still littered with evidence of that historic event. The coast is lined with vast concrete structures, which have not only endured war, but time. The largest bunker on Utah Beach today is the R612 casemate, an enormous structure with walls up to 2 meters thick!

This bunker is part of the WN10 hardpoint, which engaged American troops as they landed on the shore early on the morning of June 6, 1944. The R612 bunker was hit by naval gun fire, but could not be put out of action.

Today, we are taking you on a tour through this concrete behemoth, where you will see how it works, and what it looks like now.

Utah Beach

Utah Beach was one of the five beaches selected as the arrival point of the Normandy landings in June 1944. Situated around 20 miles from the port city of Cherbourg, Utah was the most northern beach and one of two, alongside Omaha, assaulted by US forces.

Utah beach was strategically important, as it would enable Allied forces to cut off the Cotentin Peninsula, severing the critically important port of Cherbourg off from the rest of France.

Men, equipment and supplies after landing on Utah Beach.

Predicting that the beaches of Normandy were a potential Allied landing zone, Field Marshal Erwin Rommel began reinforcing the area with bunkers, troops, barbed wire, mines, beach obstacles and even floods.

Further inland, gun batteries were built; these contained larger guns which, in the event of an invasion, would fire onto the beaches or target enemy ships at sea.

On Utah beach itself, a series of hardpoints were constructed. These were called Widerstandsnest (“resistance nest”), known as “WN” for short, and given a number for identification. The beach’s defences stretched 13 miles from WN1 in the south, to WN21 near Quinéville.

Utah Beach after the landings. The line of ships on the left were sunk to create an artificial breakwater.

WN10 Hardpoint

Slap bang in the middle is WN10, a hardpoint complex near Saint-Martin-de-Varreville. Today it is one of the most complete and extensive defences on the Normandy beaches with around 20 bunkers in a relatively small area.

The fortifications here range from mortar bunkers to machine gun nests, tank-turret bases, and large caliber gun casemates.

These casemates are positioned to enable “enfilading fire”, which is where guns are situated to fire along the line of defense, rather than directly at the enemy.

The Vf (left) and R676 (right) bunkers at WN10. The Vf is the older of the two, but both point along the beach, not out to sea.

Guns in enfilade can cover a much greater area along a front than if they were pointing perpendicular to their line. They also compress a wide target, such as a beach, into a smaller area.

In addition to this, the opening of the bunker cannot be fired upon from the enemy’s own direction of travel, as the side facing them acts as a natural shield. Positions in enfilade are also easier to hide.

On the Atlantic Wall, bunkers in enfilade are positioned to cover each other’s blind spots, or create overlapping fields of fire.

WN10, as seen on September 15, 1944. Surprisingly little has changed.

WN10 does the same. One of the earliest bunkers here faces to the south and would have once housed a 4.7 cm Skoda gun.

Directly next to it is another R676 4.7 cm Skoda gun bunker that also faces south – this was a newer type built to replace the original.

This view shows emplacements positioned on top of the dunes, running along WN10.

A few dozen meters behind the dunes is a mortar bunker, a six-man personnel bunker and a number of tobruks (small, one man bunkers).

Around 200 meters north is the centrepiece of WN10, a large casemate that sits right on the beach on the edge of the dunes.

Although well known locally, this particular bunker is not a popular destination for visitors – even though it’s one of the closest to what people expect of bunkers on the Normandy beaches. This is likely because it is a few kilometers from the more popular Utah Beach Landing Museum area.

The R612 casemate on Utah Beach.

Regelbauten 612

This bunker is an R612-type casemate. In the 1930s, Germany created a standardised list of bunker types known as “Regelbauten”, to streamline supply chains and simplify construction. This list contained a variety of bunkers of different sizes, protection levels and layouts to suit a wide range of locations and purposes.

Standardising bunker construction allowed for better allocation of resources, as the required amount of raw materials were already known, and sped up their construction time. This meant that a Regelbau bunker of the same type would be, for the most part, identical, whether they were in Norway or the south of France.

Plan drawing of the R612’s layout and wall thickness. Image credit: www.regelbau.dk

The R612 on Utah is a standardised design, indicated by its name: R=Regelbau and 612=the standardised type.

The R612 was a “Ständig” (St) category bunker, this meant its protection levels were between 1.5 meters and 2 meters of concrete. St bunkers could also feature a number of additional defences, including fake vents, gas-proof air ventilation, and stepped openings.

R612 bunkers are of the casemate type, so there is an opening in the front for a large caliber weapon. The bunker is just over 5 meters tall and 15 meters long, and was filled with around 385 m³ of concrete. The concrete is reinforced with 17 tons of rebar to greatly increase its strength.

Top-down view of the R612 bunker on Utah. Note the large wall on the upper right corner – this guards the gun opening against fire coming from the sea.

The armament contained within this type of bunker varied depending on the availability of ammunition or the guns themselves, but they would have ranged from 7.5 cm to 10.5 cm weapons.

It’s layout is rather simple: the firing room is located at the front of the bunker, with an embrasure (opening) for the gun to fire through, two ammunition storage rooms behind this, and a doorway at the rear.

Externally, the main structure of the bunker is a cube, but three of the four corners are extended outward to shield the bunker from different directions. The largest shield is to the left of the gun opening (when looking at the front), this thick wall protected the front of the bunker against protectiles coming from the direction of the sea.

The gun opening is relatively small, and can only be attacked from directly in front as it’s protected by the concrete wall on the left.

The R612 on Utah Beach

The R612 of WN10 is the biggest bunker on Utah beach, and a perfect example of Germany’s approach to defending the European coastline.

It sits right on the edge of the dunes, facing north along the beach, not out to sea. This is in enfilade, as mentioned earlier, and allowed this bunker to cover a wider area of beach and hit the enemy in the side, all while being protected from naval gunfire.

You’d need to be further north to get a shot into the opening, whether that’s on the beach, or further up the coast on a ship.

The access doorway at the rear of the bunker. When in service, this would have had two large steel doors. Also, note the damage to the bunker – this likely occurred after D-Day from forces attacking its rear.

Inside, the bunker has quite a simple layout, typical of the 612 type. It has one large chamber, which starts at the rear entrance door and ends at the gun embrasure at the front.

Today the rear entrance is open, but it would have once been sealed by two thick steel doors. The framework for these doors can still be seen.

Entering into the bunker, you are immediately flanked by two ammunition rooms. These could have stored up to 500 rounds of 7.5 cm ammunition.

View into the R612, looking toward the gun opening at the front of the bunker. Note the two ammunition rooms either side of the image.

After this you are immediately inside the triangular-shaped “combat room”. This triangle shape gave the gun the maximum lateral movement inside the bunker, while keeping the embrasure relatively small.

In 1944, the combat room would have contained a 7.5cm Feldkanone 38.

There are a number of curved channels on the floor of this room – these meshed with the gun’s mount for different firing positions.

This bunker would have contained one of these, a 7.5cm Feldkanone 38, on D-Day.

Also in here are the rusty remains of the ventilation system, which would have once served to extract the gasses from firing the gun out of the bunker.

The outside of the bunker still bares the scars it received on D-Day. The largest of these are on the sea-facing side, and range from 5-inch shell impacts, all the way down to small arms fire.

Naval gun impacts on the sea-facing side of the bunker. These hits were likely made by USS Hobson, which fired on WN10 on D-Day.

Despite the power of these naval guns, they did little more than dent the bunker, and did not put it out of action on D-Day.

It also shows how the enfilade position and shielding wall worked exactly as intended, as the vulnerable gun opening could not be hit from the sea.

One interesting feature of this particular bunker is the addition of a defensive machine gun port on the left side. These was not part of the Regelbau 612 design, so this was something planners at the time deemed necessary to add.

The non-standard machine gun port on the left side of the bunker. This was likely added to give the bunker some close-range defense.

This R612 on D-Day

As a bunker that was center stage of the largest seaborne invasion in history, it naturally had a heavy involvement on that day.

The Allies planned to land troops on two sections of Utah Beach; named Uncle Red and Tare Green, beginning at 6:30 AM. The original location for these sections would have put the troops directly in front of heavily defend WN8 and WN9 hard points.

However, the landing craft carrying the men and equipment in the first wave were pushed south by strong currents, so they actually ended up landing in front of a less-well defended position (the Utah Beach Landing Museum marks this location).

Period photograph of the R612 on Utah. Note the concrete wall running alongside the bunker – only remnants of this wall remain today.

Theodore Roosevelt Jr., who was in the first wave, requested that the rest of the landings take place here rather than the original location. As a result, WN10 was not likely to have been attacked by assaulting troops immediately, but it still received quite a battering from gunfire.

It seems most of this fire came from USS Hobson, who guided the first wave of landing craft to the beach.

She then began firing at her assigned target of WN9 with her 5 inch guns. She was at such close range that she could see her targets clearly and was firing at them directly.

Hobson then began firing at WN10 at around 7:00AM, so the large impacts on the side of the R612 bunker are likely from Hobson’s 5-inch guns.

Expended cartridge cases on the deck of USS Hobson after firing on Utah Beach, on D-Day. Some of these rounds may have struck this R612,

Despite this, the R612 was not silenced on D-Day.

The crew operating the bunker held out until dark, where they then left under the cover of dark. Not aware of this, American Shermans from the 746th Tank Battalion launched an attack on WN10 in the days following D-Day.

This attack came from the south, behind the bunker, and the evidence of this can still be seen today. There are large amounts of impacts on the rear of the bunker, including holes made by tank rounds. We actually measured these, and they checked out as 75 mm – the caliber used by the Sherman.

WN10 was soon taken by Allied forces.

One of the 75 mm-wide holes in the rear of the R612 bunker. These shots likely came from Shermans of the 746th Tank Battalion, approaching the bunker from the south.

WN10 would have another moment in the spotlight a few months later, as it was the exact location the French 2nd Armored Division, under the command of General Leclerc arrived in France.

Today, this bunker still sits silently, now guarding the coast against erosion, rather than an amphibious invasion. Next to WN10 is a large memorial dedicated to the French 2nd Armored Division. Surrounding this memorial is an M8 Greyhound, an M3 half-track and an M4A2 Sherman.

It’s a great location to visit, as in this one spot you can see a well preserved Widerstandsnest and a handful of famous Second World War vehicles.