Thiers wall

The Thiers wall was the last of the defensive walls of Paris. It was an enclosure constructed between 1841 and 1844 under a law enacted by the government of the French prime minister, Adolphe Thiers. It covered 7,802 hectares , along the "boulevards des Maréchaux" of today. A sloping area outside the wall, called a glacis, extended outward from the Thiers wall to the location of today's Boulevard Périphérique. The wall was demolished in stages between 1919 and 1929.

Louis-Philippe, proclaimed king of the French in 1830, was convinced that the key to defence of France was to prevent Paris from falling too easily into the hands of foreign armies as happened during the Battle of Paris in 1814. So he conceived the project of building around the city an enclosure of walls that would make the city impregnable.

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