- Only today does the Kossava abate in Serbia, allowing the flow of men and supplies across the Save and Danube Rivers to resume. South of Belgrade, with the Germans and Austro-Hungarians pushing across the Avala Hills, General Živojin Mišić, commanding the Serbian 1st Army, orders a retreat southwards to a new line of hills centred on Kosmaj Mountain, covering the Kolubara River and the town of Valjevo. During the day, the Serbian divisions under his command disengage and pull back seven miles to the new line by nightfall. The pursuit by the Austro-Hungarian 3rd Army is slowed by the poor state of the roads in the aftermath of the Kossava and the destruction of several viaducts cutting the only railway south of Belgrade. To the east on the front of the German 11th Army, after two days of fighting German forces push through a new Serbian defensive line on the Sapina Hills running through Smoljinac and Makci, with 107th Division seizing the former and X Reserve Corps capturing the latter.
|The advance of the German 11th and Austro-Hungarian 3rd Armies, Oct. 17th to 22nd, 1915.|