The 'F-Linie' was a German fallback position for General Sigfrid Henrici’s (from 8 April 1944 General Maximilian de Angelis’s) 6^th Army of Generaloberst Josef Harpe’s Heeresgruppe 'A' in the southern sector of the Eastern Front within the context of the army group’s withdrawal along the Bolshoi Kuyalnik river between the Yuzhny Bug and Dniestr rivers (early April 1944).