Course à la mer
The plan was implemented from 7 August 1914, with disastrous consequences for the French, who were defeated in the Battle of the Frontiers at a cost of The French armies (and the British Expeditionary Force) in Belgium and northern France were forced into a retreat as far as the Marne river, where at the First Battle of the Marne the German armies were defeated and forced to retreat to the Aisne river, eventually leading to the Race to the Sea.