Series Number Id: GSGS 3390. Sheet number: part of sheet 51. Battle of Arras preparations; trench, target and hostile battery map. "3rd Field Survey Co. RE. (1404)". "Ordnance Survey, February 1917." Grey base map; German trenches and names red; British trenches to depth of 300 yards blue. Overprint in dark blue-purple: "Artillery" [target and hostile battery reference] with artillery details. Overprint in green: [Enemy Organisation] Reference, showing railways, roads and tracks chiefly used, and more., Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC24; envelope_number: 731.