The defining feature of the Western front was a long trench system that ran from the North Sea through Belgium and France to the Swiss border. In September 1914, the Germans began entrenching themselves in the portions of France and Belgium they had captured. The Allies, unable to break through this line, started digging trenches as well. Despite major offensives, this line remained more or less static until 1918, with neither side progressing more than a few miles. In the spring of 1918, the Germans made an advance of nearly 60 miles to the west in their Spring Offensive. However, Germany's manpower was now depleted and it was facing economic and social issues. The Allies managed to break through with the Hundred Days Offensive beginning in August 1918, resulting in Germany signing an armistice on November 11.