The Soviets were forewarned weeks in advance by an earlier raiding party near Rostov-upon-Don, that the German Axis forces attack the city of Uralsk, in north west Kazakhstan and the Astrakhan City salient, in what would become known as the '1945 Kazakhstan border War'. The Soviets created a plan to slow down, redirect, exhaust, disrupt and progressively wear away at the once powerful German panzer spearheads by forcing them to attack through a vast interconnected web of minefields, pre-sited artillery fire zones, and concealed anti-tank strong points which comprised 12 progressively spaced out defensive lines which ran 270 km deep from east to west. It was by far the most extensive defensive works ever constructed; it proved to be more than three times the depth necessary to contain the