21. The 262nd Reserve Regiment history writes that its trench system was " lost in a crater field ". 22. A trench system was built outside the camp in which the division practiced the techniques of trench warfare. 23. Consolidating the third-line proved difficult under relentless bombardment and determined opposition from the uncaptured right of the trench system . 24. The Germans recaptured the Hohenzollern trench system on 3 October, and the new attack was aimed at this point. 25. The front bunker of a trench system usually includes machine guns or mortars and forms a dominant shooting post. 26. Machine guns protected within casemates, on top in Tobruk pits, or in trench systems , some with thin overhead protection. 27. It is an active, initial back-arc rifting basin which has formed behind the Ryukyu arc-trench system in the West Pacific. 28. Work began on another defensive position in the autumn of 1917, with the original Hindenburg Line as its front-trench system . 29. Very early in the war, British defensive doctrine suggested a main trench system of three parallel lines, interconnected by communications trenches. 30. Under covering fire from his tank, Sgt Hurwitz and the two men with him cleared three buildings, and elaborate trench systems .
