The (Hunding Position) was to run from Péronne to Etain, north-east of Verdun behind the Champagne battlefields of 1915. The (Michel Position) was to cover Etain to Pont-à-Mousson behind the St Mihiel Salient. The new fortified areas were intended to be precautionary measures () built to be used as rallying-positions (, similar to ones built on the Russian front) and to shorten the Western Front to economise on troops and create more reserves. The had the potential to release the greatest number of troops and was begun first; Hindenburg and Ludendorff decided its course on 19 September and construction began on 27 September.