Series Number Id: UNKNOWN. Sheet number: part of Sheet 51. East of Vimy Ridge, artillery map. "[German] trenches corrected to 12-5-17." "[Enemy battery] positions corrected to 15-5-17" in black overprint. "1st Field Survey Co. R.E. 2167 [numbers crossed out and replaced with black overprint] 2211." Overprint in green, blue and yellow showing enemy batteries, targets, harassing fire and more. Detail, grid and contours grey; German trenches red., Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC16; envelope_number: 430.