{"id":85117,"date":"2025-07-24T20:01:04","date_gmt":"2025-07-24T18:01:04","guid":{"rendered":"https:\/\/centcols.org\/?p=85117"},"modified":"2025-08-26T14:31:52","modified_gmt":"2025-08-26T12:31:52","slug":"blue-line-challenge","status":"publish","type":"post","link":"https:\/\/centcols.org\/en\/challenge-de-la-ligne-bleue\/","title":{"rendered":"Blue Line Challenge"},"content":{"rendered":"
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Bernard Pommel (CC N\u00b03094) is proposing this challenge.<\/p>\n<\/blockquote>\n\n\n\n

This Challenge consists of crossing all 41 passes (surfaced and unsurfaced) on the Franco-German border as it was drawn between 1871 and 1918, following the tragic war of 1870.<\/p>\n\n\n\n

History of the Franco-German border (1871-1918)<\/h2>\n\n\n\n

The Franco-German War of 1870-1871 had its origins in national and dynastic rivalries between the France of Napoleon III and Prussia led by Otto von Bismarck. Bismarck sought to unify the German states under Prussian leadership, thereby consolidating German power in Europe. The opportunity came with the candidacy of a Prussian prince to the Spanish throne, perceived by France as a threat to its influence. The Ems dispatch, skilfully modified by Bismarck to appear offensive, exacerbated tensions and prompted Napoleon III to declare war in July 1870.
Ill-prepared and poorly commanded, the French army suffered heavy defeats, notably at Sedan in September 1870, where Napoleon III was captured. The Prussians laid siege to Paris, which capitulated in January 1871 after months of hardship. The conflict ended with the proclamation of the German Empire in the Hall of Mirrors at Versailles, a symbolic act that humiliated France. The Treaty of Frankfurt signed on 10 May 1871 imposed heavy financial reparations on France and the loss of Alsace-Lorraine, exacerbating lasting hostility between the two nations. This war marked a geopolitical turning point in Europe, laying the foundations for the tensions that would lead to the First World War (notion of \"revanchism\", \"Always think about it, never talk about it\").
On the French side, Aim\u00e9 Laussedat, a polytechnic engineer, was largely responsible for the precise design of this new boundary. This process, which was sometimes conflictual, required negotiations to adapt the line to geographical realities and local interests.
La nouvelle fronti\u00e8re impos\u00e9e par le trait\u00e9 de Francfort, longue d\u2019environ 500 km, d\u00e9marquait brutalement la France de l\u2019Allemagne. S\u2019\u00e9tendant des Vosges au nord jusqu\u2019au Rhin, elle traversait des paysages vari\u00e9s : plaines, for\u00eats et montagnes. Cette ligne, marqu\u00e9e par 4056 bornes num\u00e9rot\u00e9es (dont une partie existe encore) et des rep\u00e8res g\u00e9ographiques (poteaux), isolait les territoires annex\u00e9s, incluant Strasbourg, Metz et Mulhouse, dans l\u2019Empire allemand. La fronti\u00e8re suivait parfois des \u00e9l\u00e9ments naturels, comme des cours d\u2019eau, pour faciliter son identification. \u00c0 partir du Donon et jusqu\u2019au ballon d\u2019Alsace, elle suivait la ligne de cr\u00eate des Vosges (la \u00ab ligne bleue des Vosges \u00bb, Jules Ferry ; cette expression \u00ab ligne bleue des Vosges \u00bb prit ensuite le sens de \u00ab la fronti\u00e8re franco-allemande \u00bb).
However, it also cut off villages and communities, breaking existing cultural and economic links. This demarcation, perceived as an open wound by France, symbolised a loss not only of territory but also of identity.
This border disappeared \"de facto in 1918 with the entry of French troops, and de jure with the Treaty of Versailles in 1919. But in reality, the border as such disappeared as early as 1914, in the fighting of the First World War\". (Benoit Vaillot)<\/p>\n\n\n\n

Bibliography<\/h2>\n\n\n\n