Series Number Id: GSGS 2742. Sheet number: 36 NW. Edition number: 9a. "Trenches corrected to 26-6-18." "Note change of colour - German trenches blue"--shows all trenches in the Armentieres region, including old British System (captured by the Germans in April 1918). "Ordnance Survey, Aug, 1918.", Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC26; envelope_number: 766
