Hitler's Fortresses in the East

‘Fortresses must carry out the same tasks as the fortresses of old….They must allow themselves to be surrounded and thus tie down as many enemy forces as possible.’ So Hitler directed in March 1944 and, in so doing, sealed the fate of Ternopol', Kovel', Poznan and Breslau, cities in the Ukraine and Poland that were in the path of the Red Army’s advance towards Nazi Germany. German forces, under orders to resist at all costs, adopted all-round defence and struggled to hold out while waiting for r