At the beginning of 1944, the western half of the Winter Line was being anchored by Germans holding the Rapido-Gari, Liri and Garigliano valleys and some of the surrounding peaks and ridges. Together, these features formed the Gustav Line. Monte Cassino, a historic hilltop abbey founded in AD 529 by Benedict of Nursia, dominated the nearby town of Cassino and the entrances to the Liri and Rapido valleys.