Hot spots on the Swiss border (1914-1918)

Where WW1-front lines reached Switzerland

By Oswald Schwitter


The portal of Burgundy (trouée de Belfort/Burgunder Pforte) was often the theatre of military operations in the past centuries – being the classical passage between Rhine and Rhône River. After the French-German war of 1870/71, the German Empire had annexed the Alsatian territories and established the new border to France near the fortifications of Belfort.

WW1 was going to change that border again – after 4 long years of terrible fighting.

The map below gives an overview of the first attacks in 1914, the establishment of the front line between Nieuwpoort in Belgium and the Swiss border after the Battles on the Marne, the front line at the armistice on November 11th, 1918 and the areas I+II for demilitarization.


ill. 1: Overview of the Western Front; the Swiss-Alsatian area is marked.


After 1871, the borders of France (F), Germany (D) and Switzerland (CS) met in the forest between the villages of Réchésy (F), Beurnevésin (CS) and Pfetterhausen (D).


ill. 2: boundary-stones at the "point of 3 countries" (borne des 3 puissances/Dreiländerstein) in August 1914. The stone on the left marks the border between France and Switzerland. The stone on the right marks the border between France and the German Empire. (See map of ill. 6) It carries the number 4056, was placed on September 28th, 1871 and it corresponds to the number of such stones placed between Luxemburg and here to mark the new borders of the German Empire – then including Alsace and Lorraine.



ill. 3: boundary-stones at the "point of 3 countries" in September 2000.
The stones have not been changed - but this photo shows also the remains of a 3rd stone on the right, dating back to the Middle Ages when the border between the territories of the bishop of Basle and the county of Pfirt (Habsburg/Austrian after 1324) was here.


On actual maps, the former border between France and the German Empire in Southern Alsace from Mount "Ballon d’Alsace" (North of Belfort) to Réchésy on the Swiss border corresponds to the actual departmental borderline.

Note: The events leading to the outbreak of WW1 in August 1914 and the various dates of the declarations of "state of war" are supposed to be generally known.

In German Alsace, the "state of attention" was declared on July 31st, 1914.

Mulhouse (Muelhausen) was the garrison of the 58th infantry brigade (112th and 142nd regiment), the 5th regiment of mounted riflemen and the 22nd regiment of cavalry. All these troupes were part of the XIV Army corps of Baden. Together with the XV Army corps near Colmar and another Army corps plus 4 territorial brigades they formed the 7th German Army under the command of General von Heeringen.

On July 31st, 1914 the Inf. Reg. 142 occupied his area with outposts on the line Cernay (Sennheim) – Dannemarie (Dammerkirch) – Swiss Border. The regiments of cavalry and mounted riflemen reinforced the customs officials and patrolled in the border area.

Around Belfort, the French 7th Army corps under General Bonneau consisting of the 14th and 41st infantry division, reinforced by the 8th cavalry division, was part of the 1st French Army of General Dubail with headquarters at Epinal. The original mission for the 7th Army corps - according to the French "plan XVII" - was to cover the mobilization of the fortress of Belfort, the railroads to Paris and the pass roads of the High Vosges (from Col de la Schlucht on southwards). Bonneau placed (a) the 8th cavalry division plus a battalion of the 44th infantry regiment between the Swiss border and the Rhine-Rhône channel under the command of General Aubier, (b) the 14th infantry division between this channel and the Vosges mountain chain under the command of General Curé and (c) the 41st infantry division in the Vosges between the Col des Croix (NW of Ballon d’Alsace) and Gérardmer.

The Swiss territorial forces occupied the border positions on August 1st, 1914 while the Swiss Army was mobilized for Monday, August 3rd, 1914 with a front NORTH between the Lake of Neuchâtel and the Lake of Constance. The 2nd and 4th cavalry brigades were sent on August 5th, 1914 to the critical Ajoie region around Porrentruy.


ill. 4: Disposition of forces in Alsace on Aug. 4th, 1914


The German Empire remitted the declaration of war to France on August 3rd 1914 and invaded Belgium one day later. (See map of ill. 1)

In spite of that German operation, the French High Command under General Joffre maintained the ideas outlined in "Plan XVII" to attack in Lorraine on August 14th, 1914 with the 1st Army Dubail on Sarrebourg and with the 2nd Army Castelnau on Morhange. To protect the right flank of the 1st Army, the 7th Army Corps Bonneau should previously attack in Alsace and rapidly reach Mulhouse, Colmar and Sélestat.

On August 7th, 1914, General Bonneau started the 1st attack on Mulhouse with about 40’000 men and 3 regiments of field artillery – after having expressed heavy doubts regarding a German superiority due to the presence of their XIV and XV Army Corps.

Various engagements and a serious fight at Altkirch on the Ill river reduced the speed of the French advance against the withdrawing Germans, so that the town of Mulhouse was only occupied in the evening of August 8th.

On Sunday, August 9th, the German counter-attack started with the XV Army Corps (von Deimling) coming from the area south of Colmar and the XIV Army Corps (von Hoiningen) coming from Müllheim via the forest of the Hardt. Heavy fighting on a line between Cernay (Sennheim) and Rixheim lasted all day.

In the night, General Bonneau ordered the retreat of his troupes to the line Thann – Schweighouse - Illfurth. On the 10th, the Germans attacked with success on that line, especially in the middle, so that the 7th French Army Corps continued to retire in the direction of Belfort. On Tuesday morning the French line was back at Dannemarie (Dammerkirch) – Masevaux (Masmünster) and the retreat continued. The Germans followed them with cavalry, artillery and infantry on horse-tracked vehicles and had many skirmishes.

A fight around Montreux-Jeune (Jung-Muensterol) east of Belfort opposed the 113th French reserve brigade and the 2nd grenadier regiment Nr. 110, reinforced by artillery, during the full day of August 13th, causing over 350 dead and wounded on the German and over 800 on the French side.

On August 14th, 1914 the XIV Army corps was ordered back to Müllheim and transported to Strasbourg, to be used with the 7th German Army. The XV Army corps was also ordered back to Strasbourg.

These troupes were replaced by a group of 5 reserve brigades under the command of General Gaede, consisting of 21 infantry battalions, 5 cavalry squadrons and 10 batteries of artillery.

The French High Command was dissatisfied with the loss of Mulhouse and created already on August 10th a new army under the command of General Pau. It consisted of the 7th Army corps, the 8th cavalry division and the 57th reserve division of Belfort (as the fired General Bonneau commanded) plus 3 reserve divisions (58th, 63rd and 66th division), the 44th infantry division and 5 battalions of "chasseurs alpins" – in total about 150’000 men, called "Armée d’Alsace" or "7th Army".

The orders for this new 7th Army remained the same as for the first attack: protect the right flank of the 1st Army in Lorraine by a new attack on Mulhouse, Colmar and Strasbourg, throwing back the German troupes to eastern side of the Rhine river.

For General Pau, whose troupes were back at a frontline between Masevaux and Montreux – at the old border of 1871 – a difficult task.

However, on August 14th, the Germans took urgently back their troupes – as mentioned above – and General Pau decided to follow them immediately, progressing between the Col de la Schlucht and the Swiss border. The general advance was slow and the French troupes reached only on the 18th the line Seppois – Dannemarie – Reiningue – Soppe (Sulzbach) and Munster in the Fecht valley.

For August 19th, General Pau planned to attack in the south the city of Mulhouse and in the north the city of Colmar at the exit of Fecht valley.

For General Gaede, the main task with his 5 reserve brigades was to keep the bridges over the Rhine river. Only cavalry and cyclists patrolled in the area of Mulhouse and the Vosges mountains. A single detachment kept the valley of the Fecht river near Munster (W of Colmar).

On August 19th, 1914 the Germans 6th and 7th armies in Lorraine stopped their fake retreat and started on the 20th a counter attack on Sarrebourg and Morhange against the French armies of Dubail and Castelnau.

Therefore, it was important to keep the French troupes in Alsace busy – and that’s why Gaede had to attack the 7th French army around Mulhouse on the 19th

On the line Mulhouse – Altkirch, the troupes clashed together in very heavy fights.

North of Mulhouse, the French reached Wittenheim-Illzach and could occupy Mulhouse again. (General Gaede lost 2300 men and 24 cannons on that day.)

West of Colmar the French reached the village of Trois Epis on the 19th and on the 20th Turckheim/Ingersheim at the exit of the Fecht valley. On August 21st, 1914, French soldiers even patrolled in the evacuated city of Colmar.

In the "trap" in Lorraine, the two French armies had terrible losses from the German counter attack and were forced to withdraw. Immediate help was needed – but only the "Armée de l’Alsace" could become available when giving up again the town and surroundings of Mulhouse. General Joffre decided that the 7th Army had to give up the Alsatian plain and to go back to the Vosges mountain chain – however, without the 7th Army Corps and the 63rd infantry division who should form the core of a new 6th French Army near Paris.

On August 24th, 1914 the 7th Army left the area of Mulhouse and withdrew to the borderlines of 1871! Only a day later, the governor of Belfort was ordered to destroy the bridges of Illfurth and Aspach, the sluices of the Rhine-Rhône channel and the 2 beautiful railway viaducts at Dannemarie.


ill. 5: Viaduct of Dannemarie


Already on August 7th, 1914 during the 1st attack on Mulhouse, about 400 men (infantry and cavalry) had attacked with success the German troupes at Pfetterhouse next to the Swiss border. The French were able to keep that position in spite of the two following retreats so that it formed the cornerstone of the final frontlines.


ill. 6: Local French attack on Pfetterhouse of August 7th, 1914.


After the French retreat from Mulhouse on August 24th, 1914, the troupes of General Gaede followed up to Dornach, just west of Mulhouse – and then pushed the lines in September 1914 forward to Altkirch – Bisel – Mooslargue. During that period, patrols had many skirmishes and a serious fight on Sept. 9th – 11th for Aspach - Michelbach.

On the other side, the fortress of Belfort disposed of 70’000 men of which the brigade of General Rouquerol blocked the road from Belfort to Cernay.

During September 1914, the French troupes advanced again to a line Cernay – Aspach – Michelbach – Dannemarie – Largitzen – Pfetterhouse.


ill. 7: Southern end of the Western Front 1914-1918


French & German lines ending at the Swiss border at the Largue river northeast of Porrentruy and Swiss strong points (yellow marks) in that area.

The Swiss army had to prevent that neither the German nor the French army could gain an advantage by attacking the adversary over Swiss territory from the back – by using the convenient roads in the Largue pocket or on the Réchésy – Courtavon (Ottendorf) axis. The above map (of illustration 7) shows clearly how easy that would have been for both adversaries.

Therefore: 6 checkpoints along the border, 3 blockhouses in the Largue forest and at the Larghof-farm plus 2 observation towers were established.


ill. 8: A Swiss Blockhouse in the Largue forest, as shown on map (ill.7) above.


Today, only few traces can be found of these positions, as the following pictures - taken in September 2000 or more than 80 years later - show:


ill. 9: Bridge over the former railroad of the "International road" Courtavon – Pfetterhouse. The Swiss checkpoint Nr. 3 was situated just at the right end of this bridge. The railroad track from Bonfol to Pfetterhouse, inaugurated in 1910, formed the border.



ill. 10: The Larghof farm building with rests the former Swiss blockhouse (center) and a new, private bridge over the small Largue river (bottom). View from Northeast. Swiss map coordinates: 582’150/260’250.




ill. 11: The MOST SOUTHERN BUNKER OF THE WESTERN FRONT is this German Bunker in the wood opposite the Larghof farm. Coordinates: ca. 582’000/260’750.



ill. 12: machine-gun position next to above bunker


Swiss infantry guarded the borders and manned the strong points in the rear, while cavalry supervised the Ajoie region between Delle (France) and the line St. Ursanne - pass of Les Rangiers – Lucelle – Kohlberg (German Alsace).



ill. 13: Plan of a Swiss strong point for infantry


For the permanent observation of the areas near the border, a number of observation posts were established by the Swiss army – also on mountains of the Jura chain.


ill. 14: Typical observations posts of Mount Raemel, Blauen area south of Basel (left)
and of B.R. (Beurnevésin-Réchésy) in the Largue corner (right).


Field artillery positions to cover the area were established on Mount Terri and Col des Rangiers – the southern end of the Ajoie region.

Nearly all these "first line" positions of the Swiss army were field fortifications with wood so that few traces can be found back. However, number of trenches and strong points of the "second line", the fortifications of "Hauenstein" and around Morat/Murten (see ill. 16) built into rocks or with concrete can still be found.



ill. 15: Trenches of the strongpoint Spitzenflueli, (at the left of the red line) part of the "Hauenstein" fortification, built in 1914 with steps for riflemen, ammunition niches, shelters and gun positions. Coordinates: 627’200/246’350.


Generally, the situation for the French and German troupes at the southern end of the WESTERN FRONT remained unchanged for the coming 4 years. Guard and patrol activities, skirmishes, artillery duels changed with construction work on trenches, shelters, roads and the daily fight for survival.

However, just a few miles north – on places like Vieil Armand / Hartmannswillerkopf or Linge, bloody battles went on in an alpine surrounding. (Nearly 10’000 men were killed during the 19 days fight from Dec. 21st, 1915 to Jan. 8th, 1916 or over 68’000 men killed on Vieil Armand / Hartmannswillerkopf alone and 30’000 men killed on the Linge/Fecht valley fronts!)

Or otherwise said: "When the troupes of both sides left the Alsace after the cease-fire of November 11th, 1918 the bodies of 59’632 Germans and of 58’588 French soldiers remained there, buried on 34 German and on 56 French War Cemeteries.

For the civil population in Alsace, the 4 years after the destructions during the two "temporary liberations" were extremely difficult and miserable.



ill. 16: Memorial at the Largue bridge


The little memorial tablet is located on the road from Pfetterhouse to Mooslargue (D 24), just east of the bridge over the Largue river, on the former German frontline of 1914-1918.

It recalls the liberation of Pfetterhouse in WW2 on November 19th, 1944 (by troupes of General Caldairou) and the "Friendship and Peace" which now finally exist between these nations. Inscription:




(Before this became possible, the 2 German blockhouses of WW1, situated just about 50 meters north and south of that monument, had to fall into ruins – Alsace was occupied again from 1940 to 1944/45 – and WW2 had to be endured by soldiers and civil populations.)


In spring of 1915, with the new frontline between Italy and Austria, the situation for Switzerland changed again. The "open gap" between the Western Front and the new Southern Front (red marks on following map) could invite an attack through Swiss territory – the French "plan H" and the Italian "Linea Cadorna" confirm that such plans or fears existed.


The Swiss fortifications (blue marks below) as well as the guard posts on the borders and the areas in between continued to be occupied by the army – and the average Swiss soldier spent 450 days on duty (without wage compensation and with a meagre pay) during 1914-1918.


ill. 17: Situation of Switzerland in summer of 1915: the open gap between the southern end of the Western front in Alsace and the western end of the Italian front on the Stelvio pass (red marks) risked to invite either party to plan an attack through Swiss territory. The Swiss fortifications of WW1 are marked in blue.


A separate article (to follow) will describe the situation at the Austrian/Italian/Swiss border of the Stelvio pass/Stilfserjoch (2501m above sea level) from 1915 to 1918.

"South Tyrol / Südtirol / Alto Adige" was another 


Literature and photo credit:

- Cerf A., colonel, "La guerre aux frontiers du Jura", Payot Lausanne, 1930, 269 pages

- Cerf A./Sulser M., "Krieg an der Juragrenze", Aarau 1931, 287 pages, (ill. 2, 4, 5, 7, 14)

- Dupuy, E., "Guerre dans les Vosges, 41e div inf 1914-16", Payot Paris, 1936, 281 pages

- Fuhrer, Hans Rudolf, "Die Schweizer Armee im 1. Weltkrieg – Bedrohung, Landes-verteidigung und Landesbefestigung", NZZ Zuerich, 1999, 780 pages, (ill. 17)

- Michelin, "L’Alsace et les combats des Vosges 1914-18", vol. I, Clermont-Ferrand 1920, 128 pages

- Mittler, Max, "Am Rande der Ajoie: Zuschauer im Weltkrieg 1914-18" in "Schauplaetze der Schweizer Geschichte", pages 190-215, Ex Libris Zuerich, 1987, (ill. 6)

- Nouzille/Oberle, "Batailles d’Alsace 1914-18", Ed.Contades, 1989, 490 pages.

- Rapold, Hans, "Entwicklung der schweiz. Landesbefestigung 1815-1921" in "Geschichte der schweiz. Landesbefestigung", Orell Fuessli Zuerich, 1992, 200 pages, (ill. 8, 13)

- Schaller, Claude-Henri, "Largin", Schaller 1997, 19 pages

- Schwitter, Oswald, photos taken in September 2000 (ill. 3, 9, 10, 11, 12, 15, 16)

- Stier, H.E., "Grosser Atlas zur Weltgeschichte", Westermann, 1990, (ill. 1)


An Unfortunate Region 2003