The German Radar Surveillance around the Aber Wrach during the WW II ()
1. Introduction
The lists of the German radar bases in France of the Deutsche Atlantikwall Archiv (DAWA, 2013) and the Rapport Pinczon de Sel (Rapport Pinczon du Sel, 1947-1948; Patrimoine Region Bretagne, 2003a, b) , were useful for identifying, among other, the radar bases of Keringar Vihan, Kervingam-Kerdené and Vougo-Kerizocactive during the war for the surveillance around the Aber Wrach (Tomezzoli, 2016) . Moreover, said lists identify the kind of radars, i.e. mainly Freya and Würzburg models, in service at these bases. The Freya radar was developed in a variety of different models by GEMA (von Kroge, 1998) . It was provided in general with an instrumentation cabin sur- mounted by a rectangular, flat antenna comprising an emitter operated at 2.3 - 2.5 m wavelength, a receiver and an IFF (identification friend foe) receiver. The Freya radars were sensitive in a range of up to 200 Km and needed a power supply of about 20 Kw. The Würzburg radar was developed in a variety of different models by Telefunken. In the A, B, C, D versions it was provided with a 3 m parabolic antenna on a wheels mobile support, in the FuSE 65Riese version it was provided with an instrumentation cabin behind a 7.5 m parabolic antenna provided with an emitter operated at 50 cm wave- length and an IFF. The FuSE 65Riese was sensitive in a range up to 70 km with azimuth and elevation precision of about 0.2˚ and needed a power supply of about 160 Kw. It was usual in the German radar bases to pair Freya and Würzburg radars, the first for early warning and the second for directing the fire of anti-aircraft batteries. The Freya radars were mounted on their own supports, while the Würzburg Riese was mounted on a concrete, hexagonal support V229. In both the cases, the radars were protected by ground embankments or splitting wall emplacements.
German radar bases hosting Freya and Würzburg radars were the 2nd order Monterfil radar base “Mandrill” in Brittany (FR) (48˚03'32"N, 02˚00'33"W) equipped with 2 x Freya-Egon with goniometer, 2 x FuSE 65 and 1 x FuSE 62D Würzburg (Dupont et al., 2007) and the 1st order Les Mees radar base “Made” in Charente Maritime (FR) (48˚ 19'07.72"N, 0˚14'21.09"W) equipped with 2 x FuSE 80 Freya (with Gemse and A/N) and 2 x FuSE 65 (Tomezzoli & Pottier, 2007) .
2. FuMO 451 Keringar Vihan (Re 305?)-Radar Anti-Aircraft Base
Probably corresponding to FuMO 451 (Funk-Mess-Ortung 451-radio measuring location 451) as well as to the St.P. (support point) Re 305 (48˚21'13.95"N, 4˚45'43.10"W) (Figure 1) in the lists of the Deutsche Atlantikwall Archiv (DAWA, 2013) , the Keringar Vihan early warning and Flak (anti-aircraft) base was located near the Pointe Saint- Mathieu, on a hill about 49 m height, at only 1 km from the heavy German M.K.B. (Marine Kuste Batterie-Navy coastal battery) Graf Spee of Keringar Wraz (Tomezzoli, 2015 ). It was conceived for directing the fire of its own Flak guns and, probably, also that of the Flak guns of the Graf Spee (48˚20'40.08"N, 4˚45'07.95"W). Not mentioned by the Rapport Pinczon de Sel, the Keringar Vihan base comprised a water reservoir tank of German construction for its own water supply and that of the M.K.B Graf Spee, 2 x Flak bunkers, 2 x Freya radar emplacements and some other bunkers of unknown type and purpose. One FuMO 2 Calais B radar is identified in service at the base (DAWA, 2013) . The site visit took place on 12/09/2009.
The water reservoir tank (Figure 1, Figure 2(a)) was included in a municipal area dedicated to materials store and recycling. It was formed by a concrete tank of about 15 m in diameter placed on six concrete supports legs about 4 m height. The preservation state of its concrete structure was good without damages due to combats. Linked to conduits, it appeared still accomplishing its function of water supply. Due to its elevation and the absence of a Flak emplacement, it is possible that, during the war, it hosted on its coverage only a light machine gun emplacement and/or an observatory. A possible small bunker (2), in a cultivation field, was buried in the terrain and covered by the vegetation. Its type and purpose remained unknown. Bunker (3) (Figure 1, Figure 2(b)) about 10 × 5 m was covered by ground and emerged from the terrain for less than 1/2 m. Its entrance/s was buried in the terrain, so that its interior was not accessible,
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Figure 1. Keringar Vihan radar base-(1) water reservoir tank, (2) bunker of unknown type and purpose, (3) bunker of unknown type and purpose, (4) bunker of unknown type and purpose at the entrance of the base, (5) bunker of unknown type, probably either troop lodgment, or Flak fire control bunker, or a bunker type L406A for permanent machinery like power generators, (6) Flak bunker, (7) bunker of unknown type and purpose, (8) type 1 split wall emplacement for radar Freya, (9) Flak bunker, (10) type 5 brick, split wall version for radar Freya A Armorique peninsula, AB Aber Benoît, AW Aber Wrach, B Brest, K Kervingam-Kerdené radar base; KW Keringar Wraz M. K. B Graf Spee, KV Keringar Vihan radar base, V Vougo-Kerizoc radar base, L Lesneven [Geoportail].
and its type, purpose and preservation state of its concrete structure remained undetermined. The small, square bunker (4) (Figure 1, Figure 2(c)) about 3 × 3 m, at the entrance of the site, emerged less than 1 m from the terrain and was encircled by vegetation. Its entrance/s was not accessible, so that its type and purpose remained undetermined. The portions of its concrete structure not covered by the vegetation appeared in a good state of preservation without damages due to combats. Bunker (5) (Figure 1, Figure 2(d)) about 15 × 10 m emerged less than 1 m from the terrain and was completely covered by vegetation. Its entrance/s was buried in the terrain, so that its interior was not accessible and its type, purpose and state of preservation of its concrete structure remained undetermined. Its dimensions suggest either a bunker type R621, R622 or R656 shelters for one or two group of soldiers, or a Flak fire control bunker, or a bunker type L406A for permanent machinery like power generators, (6) Flak bunker,. The small, rectangular bunker (7) (Figure 1, Figure 2(e)) about 4 × 3 m emerged about 1 m from the terrain. An inclined ramp gave access to its entrance closed by a wood door, probably not of origin. The access of the interior was not possible, but its isolated position and reduced dimensions suggests a function of ammunition or depot bunker. The preservation state of its concrete structure was good without damages due to combats. No rests of a guard corps and a possible metallic barrier encircling the base re-
mained visible.
Bunker (6) (Figure 1, Figure 3), located on a side of the base access road, was a Vf (Verstärkt Feldmäßigen-field reinforced) or a Sk (Sondernkonstruktion-special construction) Flak bunker. It was partially covered by vegetation which obstructed its apparently unique entrance (Figures 3(a)-(c)), so that its interior was not accessible. Its
coverage, accessible through a metallic stair above the entrance, hosted a square about 5 × 5 m gun emplacement, similar to those of bunkers L409, L410, for a 37 mm Flak gun, with ammunition niches. The gun support presented a triangular shape with two square and one round cavities at its extremities of unknown purpose and no fixation joints for a gun support. The preservation state of the bunker concrete structure, in the portions not covered by the vegetation, was good without damages due to combats.
Bunker (9) (Figure 1, Figure 4), located at the end of the base access road, was a Vf or SkFlak bunker, twin of bunker (6). It was too partially covered by vegetation which fortunately did not obstruct its entrance (Figures 4(a)-(c)). Its coverage, accessible through the metallic stair above the entrance, hosted a square Flak gun emplacement like that of bunker (6). The triangular gun support presented three square cavities at its extremities and gun support fixation joints disposed along a circle. The visit of the interior showed that it was composed by a large, single room deprived by all the original furniture and no traces of thermal insulation. Its floor was partially invaded by water. The preservation state of the bunker concrete structure, in the portions not covered by the vegetation was substantially good, with the exception, on one side, of impact cavities (Figure 4(b)) due to projectiles of small or medium caliber gun.
The hexagonal bunker (8) (Figure 5) was a type 1 concrete, split wall emplacement for Freya radar. The owner of the site, born after the war, therefore an indirect witness, declared that at its origin the bunker was uncovered and that it hosted a radar device, but he appeared also puzzled by the news received by a relative that, during the war, the Germans had no radar. The bunker, was arranged as hen-house and workshop, and presented, in the portions not covered by the vegetation or agriculture materials, a concrete structure in a good preservation state without damages due to combats. The visit of the interior showed a well preserved concrete floor with no V229 support for FuSE 65, which confirmed that it hosted the Freya FuMO 2 Calais B radar (DAWA, 2013) mounted on its leg metallic support. On the floor, some original grooves, probably for radar cables connections, were filled with concrete by the owner after the war. The upper side of an interior wall presented impact cavities (Figure 4(d)) due to projectiles of small caliber machine gun. The owner declared that the nearby bunker (10) had, during the war, the same function of bunker (8), suggesting the presence, actual or foreseen, of another Freya radar at the base.
The rectangular bunker (10), about 10 × 5 m, was a type 5 concrete, split wall emplacement for Freya radar. Its interior, completely filled by debris and vegetation, was inaccessible and, consequently, it was not possible to ascertain whether, on the contrary, it contained a support V229.
The search on the terrain for V229 supports and for traces of possible disappeared wooden barracks hosting soldiers’ lodgments, a canteen, kitchen and latrines gave no result. A possible estimation to about 50 the number of the personnel members in service at the base is rather uncertain.
Two split wall emplacements and only one radar identified suggest that the base was probably not completed at the retreat towards the Festung (fortress) Brest of the German troops. Two radars at the base is not surprising in order to operate one of them for surveillance during the periods in which the other was under reparation or maintenance.
However, a bit surprising is the absence of a Würzburg radar for precisely direct the fire of the Flak guns of the base. It is also not clear from where the power supply for the radar/s arrived, i.e. either from the French power network or from German power generators.
3. FuMG381 Kervingam-Kerdené-Radar Base
Indicated as FuMG381 Kervingam in the lists of the Deutsche Atlantikwall Archiv (DAWA, 2013) and as Kerdené radar base by the Rapport Pinczon de Sel (Patrimoine Region Bretagne, 2003a) (48˚38'20.64"N, 4˚11'47.7"W) (Figures 6-10), this radar base comprised one radar emplacement and one or two observatories. One FuSE80 Freyaradar is identified in service at the base (DAWA, 2013) . The site visit took place on 25/09/2016.
The 10 × 8 m type 5 stone brick, split wall emplacement for Freya radar (Figure 7) was about 2 m high and 1m thick, and its entrance was protected by a wall about 1 m high and 1m thick. It was built around a preexisting two roomshouse of which only the foundations remained visible. Due to its reduced dimensions (7 × 6 m) it is possible that the house hosted agricultural materials, shepherds or small cattle. The purpose of a square wall block about 1.5 × 1.5 m, between the two rooms remained unknown. The absence of a V229 concrete support confirmed that the emplacement hosted the FuSE80 Freya. The leg support for this radar was located in the space of the house. The preservation state of the bunker structure was good without damages due to combats.
About 10 meters away from the Freya emplacement, a heap of stones marked the presence of an antenna emplacement (Figure 6, Figure 8). It was constituted by a single antenna support and three concrete, cubic blocks for antenna anchoring cables. The antenna support, in its original position, presented a crumbled concrete structure due to the antenna eradication or blasting. The anchoring blocks preserving their original concrete, cubic structure and originally located far from the emplacement, were collected on the support for facilitating field cultivation. The single antenna support and the three anchoring blocks suggested a vertical telecommunication antenna of unknown type and height, which, although close to the emplacement, has not obstructed the northern coastal surveillance sector of the Freya radar.
Isolated in a field of artichokes, about 100 m far from the Freya emplacement, a heap of stones marked the ruins of a construction (3) (Figure 6, Figure 9). Its much degraded preservation state did not permitted to identify its shape and purpose. It is possible that it was a preexisting small house used by the Germans as observatory for improving the surveillance of the Kerdené coastal sector, dynamited at the retreat of the German troops.
The observatory (Figure 6, Figure 10) was a 10 × 5 m, two floors construction. The stones used for its lower floor and the bricks used for its upper floor (Figure 10(a)) suggested that a preexisting local, one floor house was elevated by one floor by the Germans and provided with an observation window. The observatory structure was rather degraded: the rear portion was collapsed and covered by the vegetation. The collapse reason, i.e. structural failure, combat damage or blasting, remained unknown.
The search on the terrain for a support V229 for FuSE 65 gave no result, indicating
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Figure 6. Kervingam/Kerdené radar base―(1) Freya radar emplacement, (2) ruins of an antenna emplacement, (3) ruins of a possible observatory, (4) residence, (5) megalithic stone circle, (6) observatory, (7) possible anti-aircraft gun emplacement [Zoom Earth].
that probably this base was an early warning radar base. If another Freya or Würzburg radar was present it was mounted on its own support and not provided with a protective split wall emplacement. The search for traces of possible disappeared wooden barracks hosting soldiers’ lodgments, a canteen, kitchen and latrines gave no result. A possible estimation to about 30 - 40 personnel members in service at the base is rather uncertain. Nobody was present on the site to whom asking information about the base and the nearby stone circle.
4. The Kervingam-Kerdené Stone Circle
It is not infrequent in visiting German military structures in Brittany to discover rests of much more ancient megalithic constructions. In the case of the Kervingam-Kerdené radar base, the visit allowed to discover, close to a residence, a megalithic stone circle or horseshoe stone circle or cromlech (48˚38'17.32"N, 4˚11'49.57"W) (Figure 11). Certainly
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Figure 9. Kervingam-Kerdené radar base-possible small observatory (3)―(a) ruins in front of the Kerdené coastal sector; (b) ruins, west side; (c) ruins, east side.
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Figure 10. Kervingam-Kerdené radar base-observatory―(a) surveilled coastal sector; (b) front side with observation window; (c) collapsed rear side covered by the vegetation.
known by the proprietors and visitors of the residence, nobody was present on the site for confirming its authenticity. Located on the top of the plateau, about 60 m a.s.l., hosting the radar base, it is not mentioned in the literature considered (Patrimoine Region Bretagne, 2003a; Burl, 1985) . It was formed by a stone circle (4) of about 12 m in diameter, comparable with the diameters of about 20 m of the similar recumbent stone circles in Scotland and Ireland. The circle was provided with a portal about 4 m wide, with, as flanker, a 2 m high menhir (2). The difference between this stone circle and the recumbent stone circles in Scotland and Ireland resides in the recumbent stone (3) of about 3 × 2 m located not on the south-west side of the circle, but rather in its internal area. No relief or other decoration was remarked on the recumbent stone and the menhir. The determination of the stone circle age was not possible, but, if authentic, according to the ages of the stone circles in Britain, Ireland and Brittany (Burl, 2000) (Burl, 2010) it could be ascribed to a period comprised between 3300 and 900BC.
The scholars advanced many theories for explaining the purpose of the stone circles: hunter houses, burial sites, meeting places, religious centres, calendars and astronomical observatories (Gibson & Simpson, 1998) . In the case of this stone circle plural purposes have been possible, together or in subsequent order, because of the evolution of the cultures that referred to it. But, the absence of the recumbent stone on the south-west side of the circle ruled out the purpose of lunar ceremonial site, typical of the recumbent stone circles in Scotland and Ireland. The presence of two stones (7) outside the circle, visible throughout the portal, would rather have addressed the attention of one or more observers on the recumbent stone (3) to the East, suggesting the calendar purpose of determining, in a sedentary, agriculture based society, the direction of the spring’s Equinox and the starting date for the spring, agriculture works. The absence of further stone landmarks ruled out a possible purpose of astronomical observatory. In any case, excavations appear necessary for establishing the circle authenticity and purpose/s.
5. FuMG398 Vougo-Kerizoc-Radar Base
Indicated as FuMG398 Vougo by the Deutsche Atlantikwall Archiv (DAWA, 2013) and as St.P. AV 24 Vougo radar base by the Rapport Pinczon de Sel (Rapport Pinczon du Sel, 1947-1948) (Patrimoine Region Bretagne, 2003b) (48˚37'30.34"N, 4˚28'5.47"W) (Figure 12), it comprised 1 × Freya radar emplacement, a L406 Abunker and some other small bunkers. One FuSE 65 Würzburg-Riese adapted for the marine surveillance and one Freya FMG40G (gB) Calais are identified in service at the base (DAWA, 2013) . The visit took place on 25/09/2016 and deserves to be told for highlighting the role played by a primary witness in investigating this abandoned radar base.
Due to the absence of road indications, two times I failed to reach the site of the radar base. In undertaking the third attempt, I decided to ask information in a farm certainly not far from it. The owner, Mr. L. Gwennec indicated me a rather complicated path for reaching the site, but added that although on the site, a visit could probably unsuccessful because many bunkers are either buried in the terrain or masked by the vegetation. However, he accepted to drive me to the site, adding that in the past the bunkers were on a part of his properties recently sold. Being known by the new pro-
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Figure 12. Vougo-Kerizoc St.P. AV 24 radar base―(1) main road, (2) narrow side path, (3) bunker L406A, (4) splitting wall radar emplacement, (5) bunkers covered by the vegetation, (6) gun emplacement (7) radar emplacement without splitting wall, (8) disappeared wooden barracks.
prietors, there was no necessity of asking permission for visiting the site. According to his indications, after a trip of several kilometres, I directed the car through a narrow side path which separated itself from the main road. He insured that no problem would arrive in travelling on said path, and, in fact, after few minutes of drive, sometimes crawling against the vegetation, we were on the site.
Mr. Gwennec, primary witness, aged of five years at the beginning of the war, asserted that there were never problems with the Germans during the period of the Occupation of France because when they were seen to arrive, all the French were leaving the place. He indicated the position of some disappeared wooden barracks (8) (Figure 12) hosting soldiers’ lodgments, a canteen, a kitchen and latrines. Then he advanced up to a bunker type L406A (3) (Figure 13), buried in the ground, for permanent machinery like power generators for the radars. The preservation state of the L406A concrete structure was good without damages due to combats. On its coverage was the opening of a tobruck and two pyramidal supports for small chimneys or vertical antennas. The interior of the tobruck was empty, without traces of thermal insulation. Materials and terrain obstructed the bunker entrances so that the visit of the interior was not possible. The garage, closed by a modern double door, was inaccessible.
Not far from the L406A, he indicated a type 1 splitter wall emplacement probably for the Freya FMG40G (gB) Calais (Figure 14). The splitter wall was covered by vegetation therefore the preservation state of its concrete structure remained unknown. The entrance was closed by a modern metallic door and thus not accessible, so that the presence or absence of a V229 for FuSE 65 was not ascertained. He did not remember the square radar antenna of the FMG40G (gB) but remembered a rotating circular radar near the splitter wall. The antenna diameter he reported, about 3 - 4 m, let think that a
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Figure 14. Vougo-Kerizoc St.P. AV 24 radar base―(a) type 1 splitter wall emplacement; (b) closed entrance of the splitter wall emplacement.
Würzburg radar smaller than a FuSE65, whose circular antenna measured 7.5 m, was present at the base. The search on the terrain for a V229 concrete support for FuSE65 was unsuccessful.
Mr. Gwennec indicated a footpath along the sea coast and declared that some bunker, buried in the terrain or covered by the vegetation, were located along it. He indicated one small bunker rather far from the pathway (Figure 15(b)). Closely surrounded by the vegetation, it was inaccessible and its type remained undetermined. He indicated a hole in the vegetation near the footpath, masking one of the corridor entrances of a bunker type R702 for a group with small gas-lock, provided with a 4 × 3 m room (Figures 15(c)-(f)). The room, deprived of all the original furniture, preserved its original white painting. The absence of traces of a chimney and thermal insulation, let think that it was not intended for lodging a group of soldiers, but rather for storing ammunitions and/or materials. He indicated a small bunker (Figure 15(g)) just emerging from the vegetation, presenting a concrete structure severely damaged. He declared this one and several other bunkers were dynamited during the retreat of the Germans troops. This declaration confirmed the execution by the German343. Inf. Div., responsible of the Finistère, of the order KR Ft 4.8.44, 11:21 (RM 45/IV 464, 1944: p. 202) , to evacuate the coasts, destroy all the Marine St.P (Stützpünkte-support points) and dynamite devices and light houses.
Concerning Vougot, the commander of the III. Marine Flak Brigadereceived and probably executed the orders of withdrawing, upon the retreat of the infantry, the Flak batteries located in Vougot, L’Aber-vrac’h and other coastal places to Brest (4.8.44, 11:30) (RM 45/IV 464, 1944: p. 202) and to held the Grèves de Vougot up to the last cartridge (7.8.44, 11:45) (RM 45/IV 464, 1944: p. 221) . The Funkmess-Abt., Ozet Bretagne received and probably executed the order KR Ft 3 of 7.8.44 to maintain the FuMO of the Greves de Vougot and others as WN (Wiederstandnest-resistance nest) at said evacuation and wait for reinforcements (RM 45/IV 464, 1944: p. 221) .
Mr. Gwennec prosecuted along the footpath up to a small gun bunker. It consisted in a well preserved, non-dynamited concrete structure comprising a circular aperture surrounded by circularly disposed gun support joints on its couverture (Figure 16(a) and Figure 16(b)). Under the couverture, a small entrance gave access to a circular room, partially invaded by the vegetation, hosting ammunition niches (Figures 16(c)-(d)). He
was not able to remember relevant details about the gun, but he told that after the war he played with it, and others, more skilled about guns, used it with recovered German ammunitions for playing to bombard some neighboring reefs.
6. Conclusion
If the visits on the sites permitted to determine precisely the actual preservation state of the radar bases considered, the memories of the witnesses have enriched this information by identifying non-evident or completely disappeared structures, adding anecdotal and historical information and confirming the recites of archival documents. It is therefore evident that this successful dual procedure should be intensified and extended to all the future studies concerning the Atlantic Wall and, in general, to all the contemporary military structures, as long as surviving primary witnesses will be available.
Acknowledgements
I wish to thank very much the owner of the site of the Keringar Vihan radar base for his kind permission of visiting the site and his information concerning its radar protective splitting wall emplacements, Mr. L. Gwennec for having ensured a successful visit of the Vougo-Kerizoc radar base site and for his relevant technical and historical information concerning non-evident and disappeared installations and Mr. B. Haas for the researches in the Bundesarchiv-Militärarchiv (BAMA) in Freiburg.