Geoff Walden


Home ] Table of Contents ] Updates ] Berchtesgaden ] Berlin ] Buchenwald ] Chiemsee Autobahn Rasthaus ] Adolf Hitler Visits Austria ] Adolf Hitler Visits Czechoslovakia ] Ebensee ] Flossenburg KZ Site ] Garmisch ] Mauthausen ] Gusen/Bergkristall ] Auschwitz-Birkenau ] Thüringen ] Mittelwerk/Dora ] Munich ] Dachau Concentration Camp ] Tegernsee ] Nürnberg ] [ Muehldorf ] Thingplatz ] End of the War in the Main-Spessart ] s.Pzjr.Abt. 653 ] Schweinfurt ] Miscellaneous Sites ] Wolf's Lair ] Mauerwald ] Anlage Mitte ] Prora KdF Resort ] Project Riese (Giant) ] U.S. Army Posts ] Nazi Eagles ] Wehrmacht Kaserne ] Hitler Visits Vienna ] Ordensburg Vogelsang ] Weimar / Dresden ] Würzburg ] Haus der Deutschen Kunst, Part 1 ] Lost Sites ] German War Memorials ] Cold War Sites ] Links ]


Mühldorf / Mettenheim

Underground Factory Project "Weingut I"


   Several underground manufacturing sites were built in the Third Reich in 1944-45, to protect vital industries from the Allied bombing campaign. Most of these sites consisted of underground tunnels, built in existing mines or new excavations (for example, see the Nordhausen, Kahla, and Ebensee pages). But a unique type of bunker was started near Mühldorf am Inn, east of Munich, called Project "Weingut I" (Wine Estate). This site was to consist of a long massive structure built from reinforced poured concrete arches. The subsurface earth would have been excavated from under the structure to provide a large working area. Design and heavy construction work was performed by the engineering firm Polensky & Zöllner, with manual labor by concentration camp inmates and Russian POWs from Dachau and other sites, who were quartered in nearby camps. (Other bunkers of this type were built near Landsberg (Weingut II and Diana II), and planned in the Sudetenland and the Rheinland.)

   The site was planned for the manufacture of Me 262 jet aircraft engines and parts, and construction began in May 1944, but the site was not completed. Only half of the concrete arches were poured, and the underlying excavation was not finished, when the war ended. Other structures in the area included air raid protection bunkers, cement factories, and administration buildings.

   The bunker structures were built by piling mounds of gravel on the ground, in the appropriate shape, and pouring concrete onto these to a thickness of three meters. The concrete was poured in separate arch sections. The finished bunker was to have consisted of twelve arches, for a total length of almost 400 meters. The underlying gravel was then excavated out, including a planned depth of 18 meters below the original ground level. An additional two meters of concrete would have been added, then earth would have been placed on top of all and planted, for camouflage.

   Construction stopped in late April 1945, when the prisoners were force-marched toward Munich (resulting in many deaths), and the U.S. Army overran the site on 2 May 1945. All but one of the seven existing arches were collapsed by explosives in 1947.

(Google Maps link)



WeingutCIOS4.jpg (468356 bytes)

This sketch shows the planned completed state. The angular structures jutting from the lower sides
of every other arch were for forced-air ventilation. The dark-tinted part is the section that was
actually erected; the other planned arches at the top were not built.  (CIOS Report, IWM)


WeingutCIOS5.jpg (336295 bytes)

WeingutCIOS2.jpg (327300 bytes)

These cross-section plans show how the earth beneath the concrete roof arches was to be excavated, providing a large work area under cover. The excavated floor would be 18 meters below the original ground level (shown as a horizontal line in both views).  (CIOS Report, IWM)


Weingut1PZ.jpg (223953 bytes)

Weingut3PZ.jpg (108923 bytes)

The bunker under construction - on the left, the gravel mound is being covered by forms for pouring the concrete. On the right, cranes are removing the fill underneath an arch section. A small train hauls the fill away. (Dr.-Ing. Günther Werner-Ehrenfeucht, "75 Jahre Polensky & Zöllner," Frankfurt a.M., Brönners Druckerei, 1955; below - U.S. National Archives)


Weingut4PZ.jpg (121616 bytes)

Weingut5PZ.jpg (114425 bytes)

Workers on the outside of the bunker prepare to pour the second layer of concrete. (above - Dr.-Ing. Günther Werner-Ehrenfeucht, "75 Jahre Polensky & Zöllner," Frankfurt a.M., Brönners Druckerei, 1955; below - U.S. National Archives)


These two views show the site as found by the U.S. Army in May 1945, with the construction cranes still in place. On the right are carloads of fill ready to be removed from the interior of the arch (compare to views of the interior today, below).  (U.S. National Archives, RG 342-FH, 3A19970 (left) and 3A19977 (right)


Note - A large memorial has been placed at this site since these photos were taken,
possibly changing the appearance from how it is shown below.


Only one of the original seven arches that were built remains erect on the site today. The remaining arches were collapsed by explosives in 1947 by the U.S. Army. This is Arch 7, which was damaged by explosives, but not collapsed. Arches 1-6 remain collapsed on the ground. The photo on the left was taken standing on the remains of Arch 5. The small protruding rods are the bases of iron reinforcements ("rebar") for a further layer of concrete on top. These rods were originally some 4-5 feet long, but were cut off after the destruction of the arches. The added concrete would have brought the total thickness to 5 meters. On the left below is a view of the site as the U.S. Army found it in May 1945.  (CIOS Report, IWM)


The remaining Arch 7 as viewed over the remains of collapsed arches 5 and 6.


Overall view of the remains of Arch 7 on the site today.


Inside Arch 7 - the ground level would have been excavated some 18 meters below the present level, to allow a larger working space.


These photos show the thickness of the concrete along the bases of the arch sides. The modern photos show the side pieces broken up during the post-war demolition.  (upper left - U.S. National Archives)


Some of the arch remains were collapsed on top of the side base pieces.


This 1945 photo shows the Arch 7 opening as it was found by the U.S. Army. The modern view shows this same corner, partially buried today.  (U.S. National Archives)


Muehldorfn3.jpg (479630 bytes)

The photo on the left shows a joint between two of the collapsed arches. The cut-off reinforcing rods can also be seen. The photo on the right shows the collapsed remains of Arch 1.



     An interesting feature that can still be found at the site (although with some difficulty - it is located about 200 meters from the remaining Arch 7) is the remains of the Entnahmetunnel, a small tunnel that was the first step in arch construction. This tunnel, the domed roof of which can be seen protruding from the ground, was built below each planned arch, with holes along its route that would allow gravel to fall through (the remaining gravel holes, which appear as flat square objects in this photo, have been filled with concrete at this site).

     After this small tunnel was complete, the gravel was built up in the shape of the arches, to make a base to pour the concrete (as described above). After the initial concrete had set, the gravel was first removed through the holes in this Entnahmetunnel, by way of a small train. After sufficient gravel had been moved this way, then the large cranes would move in and remove the rest of the gravel, as seen in the period photos above. The Entnahmetunnel would then be removed during the process of lowering the floor level to the planned depth.

     This fragment of the Entnahmetunnel was probably placed at the planned site of the final arch section (the westernmost arch), which was never begun.



Several pit structures remain on the periphery of the main site today; these were for storage, waterworks, and protection from aerial attack.


Mettenheimaerial.jpg (33606 bytes)

An airfield was built nearby, adjacent to the town of Mettenheim. In this U.S. Army Air Forces
reconnaissance photo, an Me 262 jet can clearly be seen beside the field at the top of the photo.


The Mühldorf/Weingut site is one of the most impressive Third Reich ruins sites I have visited. The site has been opened to the public as a memorial to the prisoners who died there, and tours may be arranged through the contacts below. You can also tour the site on your own, but it can be difficult to find without a guide (click here for hints on visiting this site). If you go on your own, I advise caution - due to the broken nature of the collapsed arches, and the rebar sticking up all over the place, this is a dangerous site to navigate, and it is in an isolated location out in the woods, with no residences or help nearby. (Note - Since the memorial was erected at this site, it may not be as isolated or as hard to locate as it previously was.)

You can  get a schedule of guided tours on this page (in German)  -- This page also contains much information and many photos, including photos of the destruction of the site by the U.S. Army in 1947.

The main reference is German Underground Installations, Part One of Three, "Unique Design and Construction Methods," Section II, CIOS (Combined Intelligence Objectives Sub-Committee), September 1945 (Imperial War Museum, London).

See also: Peter Müller, Das Bunkergelände im Mühldorfer Hart, Mühldorf a. Inn, Heimatbund u. Kreismuseum, 2000. Visit here  for an English translation of this book.

Dr.-Ing. Günther Werner-Ehrenfeucht, 75 Jahre Polensky & Zöllner, Frankfurt a.M., Brönners Druckerei, 1955.

Official webpage of the Mühldorf/Mettenheim/Weingut sites (in German)  --


Lstone.gif (1289 bytes)   Back to the Third Reich in Ruins homepage


Third Reich in Ruins,

All contents copyright © 2000-2021, Geoffrey R. Walden; all rights reserved.  All photos taken by or 
from the collection of Geoffrey R. Walden, except where specifically noted.  Please respect my property rights,
and the rights of others who have graciously allowed me to use their photos on this page,
and do not copy these photos or reproduce them in any other way.

This page is intended for historical research only, and no political or philosophical aims should be assumed. 
Nothing on this page should be construed as advice or directions to trespass on private or posted property.

The appearance of hyperlinks does not constitute endorsement by the author of the information, products or
services contained in any hyperlinked web site herein, and the author does not exercise any editorial control
over the information you may find at these locations.

This page initially uploaded on 20 July 2000.