Series Number Id: GSGS 2742. Sheet number: 57c SW. Edition number: 5e. "Trenches revised from information received to 23-7-18." "Enemy organisation 23-7-18". "Field Survey Bn., (10715) 27-7-18." "Ordnance Survey, April 1918.", Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC25; envelope_number: 754., Detail and grid grey; contours brown; German trenches blue; enemy organisation red. Shows all old and new trenches on the Somme Battlefield and railways, track, dumps, huts, etc.