{"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.
The new border imposed by the Treaty of Frankfurt, some 500 km long, sharply demarcated France from Germany. Stretching from the Vosges mountains in the north to the Rhine, it crossed a variety of landscapes: plains, forests and mountains. This line, marked by 4056 numbered milestones (some of which still exist) and geographical markers (posts), isolated the annexed territories, including Strasbourg, Metz and Mulhouse, from the German Empire. The border sometimes followed natural features, such as watercourses, to make it easier to identify. From the Donon to the Alsace balloon, it followed the ridge line of the Vosges (the \"blue line of the Vosges\", Jules Ferry; the expression \"blue line of the Vosges\" later took on the meaning of \"the Franco-German border\").
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