Series Number Id: UNKNOWN. Sheet number: part of sheet 36. Secret First Army railway map, May 1918. At head of map in black overprint, "Secret. Railways 15-5-18." "[First] Field Survey Co., R.E. 6066." Grey detail and squaring. Includes "Reference" to normal gauge, light railway, and metre gauge., Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC23; envelope_number: 704.
Series Number Id: UNKNOWN. Sheet number: part of sheet 36. Secret [First] Army railway map, May 1918. At head of map in black overprint: "Secret. Railways 15-5-18." "[First] Field Survey Co., R.E. 6065." Grey detail and squaring. Includes "Reference" to normal gauge, light railways, and metre gauge., Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC23; envelope_number: 705.
Series Number Id: UNKNOWN. Sheet number: part of sheet 51. Secret First Army railway map, May 1918. In black overprint: "Secret"; "Railways 15-5-18." Includes "Reference" to normal gauge, light railway and metre gauge. "[First] Field Survey Co., R.E. 6064." Grey detail and squaring., Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC23; envelope_number: 706.
Series Number Id: UNKNOWN. Sheet number: part of sheet 51. Secret First Army railway map, May 1918. Black overprint at head of map: "Secret"; "Railways 15-5-18." Includes "Reference" to normal gauge, light railways and metre gauge. "[First] Field Survey Co., R.E. 6063." Grey detail and squaring., Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC14; envelope_number: 385.
Series Number Id: GSGS 3660 [numbers in red overprint]. Sheet number: part of sheet 27. Edition number: 2. Secret allied railway map, June 1918. At head of map: Belgium 1:100,000. In red overprint: Secret, [Allied] Railways, Ed. 1, sheet no. 1. "Ordnance Survey, June, 1918." Grey and blue base map. Overprint in red, green and purple: railways legend shows standard gauge (red), metre gauge (purple), 60 cm gauge (green); treble, double, single, under construction, etc. Does not show railways in enemy area except as shown on base map. Shows heavy concentration of railways in Ypres Salient and its hinterland. Covers area from north of Ypres to south of Bethune, and from Gravelines and west of St Omer to Armentières and the western outskirts of Lille., Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC21; envelope_number: 657.
Series Number Id: UNKNOWN. Sheet number: [5]. Enemy railway intelligence map - printed at GHQ at end of war. "Printing Coy. R.E., W.O.B./2426." Grey and blue base map with black overprint. Shows 2 classes of railways, and "railways reported dismantled by two independent sources"., Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC19; envelope_number: 599.
Series Number Id: UNKNOWN. Sheet number: part of 19. Western Front, enemy railway routes, July 1918. In upper margin, in blue overprint: Ic/12215. "Printing Section, Depôt F.S.C. R.E., G.H.Q. (2176x)" in blue overprint in lower margin. Grey detail; blue water. Routes from Germany in dark blue; lateral routes in red; front line in dark blue, after German offensives of 1918.
Manuscript distribution list on verso: Hist[orical Section, Cabinet Office], DGOS [Director General of the Ordnance Survey], MI4 [General Staff, Geographical Section]., Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC17; envelope_number: 471.
Series Number Id: GSGS 2733d. "1st edition, May, 1918." In upper, right margin: sheet 1. "Ordnance Survey, May, 1918." Shows 2 classes of railway (double line and single line) in black overprint., Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC26; envelope_number: 769.
Series Number Id: GSGS 2743. Sheet number: 57c. Edition number: 2. Fourth Army enemy's railways map, 5 July 1918. At head of map: France, 1:40,000. "[5th] Field Survey Bn. R.E. (3932) 5-7-18" in black overprint. Grey detail and squaring., Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC22; envelope_number: 694.
Series Number Id: GSGS 2743. Sheet number: 66d. Edition number: 1. Fourth Army enemy's railways and enemy organisation map, 18 August 1918. At head of map: France, 1:40,000. "[5th] Field Survey Co. R.E. (3767) 9-6-18 [crossed out and followed with blue overprint] [5th] Field Survey Bn. R.E. (4171) 18-8-18." Grey detail, contours and squaring. "Enemy Organisation Map" legend, in English and French, in blue overprint., Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC22; envelope_number: 693.
Series Number Id: GSGS 2743. Sheet number: 62c. Edition number: 1. Fourth Army enemy's railways and enemy organisation map, 19 August 1918. At head of map: France, 1:40,000. "[5th] Field Survey Co. R.E. (3766) 9-6-18 [numbers crossed out and followed with blue overprint] (4170) 19-8-18." Grey detail and squaring. "Enemy Organisation Map" legend, in English and French, in blue overprint., Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC22; envelope_number: 695.
Series Number Id: UNKNOWN. Sheet number: parts of sheets 57 and 66. Fourth Army enemy's railway map, 5 August 1918. "[5th] Field Survey Bn. (3928) 4.7.18." Grey detail; overprint in black showing 3 classes of railways. "Approximate British Front Line 5-8-18" pecked black. Produced as part of the preparations for the Battle of Amiens (8 August 1918)., Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC22; envelope_number: 700.