logoSignal box prefix codes

A (hopefully) comprehensive listing

'Boxes beginning O

Last update 12 December 2018

Additional information is always gratefully received, whether entirely new records (particularly historical records), or information to fill in gaps or correct errors, via the contact link under the Miscellaneous entry in the navigation bar above.  Thank you.

Please select a starting letter from the links below:

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Code Signal Box Note ELR Mileage Opened Closed Control to
  OA&GB Junction   MVL1 6m 7ch 1965 14 January 1996 Ashton Moss North Junction (AMN)
O Oakenshaw Formerly named Oakenshaw North TJC3 182m 35ch 1928 23 December 2007 (last train);
27 December 2007 (official)
Wakefield Kirkgate [new] (WK)
OK Unclear if code carried
ON Code used when named Oakenshaw North
R Repeater signals
UM Up line automatic signals
  Oakenshaw North See Oakenshaw
OA Oakham   GSM2 93m 56ch 8 October 1899    
O Unclear whether code used
OP Oakleigh Park   ECM1 c8m 25ch 13 July 1924 30 May 1970 New Barnet (NB)
OT Oak Tree   DSN1 c4m 28ch   7 October 1972 Darlington (D)
WO Oatlands   BML1 18m 13ch 1894 22 March 1970 Surbiton [new] (S)
  Oddingley Gate box: line controlled by Gloucester (G) BAG2 62m 61ch 1908    
OF Offord & Buckden Gate box; line controlled by Peterborough (P) ECM1 55m 76ch 25 July 1976 17 May 1998 Peterborough (P)
OY Oldbury Downgraded to shunt frame 8 January 1966: line controlled by Birmingham New Street (NS) RBS2 5m 14ch   c28 October 1981 Birmingham New Street (NS)
  Old Dalby NNR   GSM4 111m 22ch ?    
OM Oldham Mumps   MPR3 7m 21ch 1967 3 October 2009 Line transferred to Manchester Metrolink
F Old Kew Junction   HOU 10m 4ch 18 October 1942 8 September 1974 Feltham (F)
LG Old Lea Station Temporary box intended for occasional use to increase capacity during Nottingham resignalling; opened and immediately switched out, never used to signal trains.  Lincoln to Gainsborough line signals SPD3 95m 68ch 30 June 2013 4 January 2014 Lincoln Control Centre (LG)
OO Old Oak Common   MLN1 2m 64ch 8 October 1962 4 September 1967 Old Oak Common [new panel] (OO)
EC Engine and carriage line signals
OO Old Oak Common [new panel]   MLN1 2m 64ch 4 September 1967 30 May 1995 Slough New IECC (SN)
DG Down goods and carriage line signals.  Code used by 1974
DM Down main line automatic signals
DR Down relief line automatic signals
EC Engine and carriage line signals.  Code used by 1971
OOO Code shown in 1984 notice in error
UC Up carriage line automatic signals
UM Up main line automatic signals
UR Up relief line automatic signals
UW Up Wycombe line automatic signals
Z Draw ahead signals at Hayes.  Code used from 10 August 1983
C Old Oak Common Carriage Line Ground Frame Believed code not carried MLN1 c2m 0ch      
CR Old Oak Common Crossrail Depot Codes shown on development plans MLN1        
WL Old Oak Common Depot Wheel lathe line signals OOC1   28 December 2017    
A Road A signals
B Road B signals
C Road C signals
OT Old Town   DSN2     26 November 1967 Middlesbrough (M)
OM Olive Mount Junction   DSE 2m 50ch 1883 18 May 1998 Edge Hill (LE)
OC Ollerton Colliery Burnt down April 2006 HIM 19m 33ch 1893 23 March 2009 Thoresby Colliery Junction (T)
OY Onibury   SHL 22m 68ch 12 December 1977   Wales Rail Operating Centre (NS) (planned)
OL Ordsall Lane No 1 Believed code not carried COL c190m 20ch   18 October 1978 Deal Street (DS)
OC Orgreaves Colliery Ambiguous source data: colliery branch removed 8 February 1981 MAC3 45m 10ch 1901 8 September 1985 Darnall West Junction (DW)
OW Orient Way Sidings Code used from opening SDC c5m 70ch 2009    
JE Orpington [panel] Code used from opening XTD 13m 49ch 4 March 1962 22 February 1993 Ashford IECC (AD)
JE Orpington 'A' Code used from 1959 XTD 13m 47ch c1904 4 March 1962 Orpington [panel] (JE)
EBV Otford Junction Code used from 11 March 1962 SBJ 24m 55ch 1 January 1898 5 June 1983 Victoria Signalling Centre (VS)
A Automatic signals
OB Oughty Bridge   MAC3 36m 23ch 24 July 1905 January 1984 Wadsley Bridge (WB)
OB Oulton Broad North   NOL 22m 1ch 1901   Colchester [new] (YL) (planned)
  Oulton Broad Swing Bridge   ESK 116m 2ch 1907 20 March 2005 Oulton Broad Swing Bridge [new]
  Oulton Broad Swing Bridge [new]   ESK 116m 0ch 20 March 2005    
OJ Over Junction   SWM2 115m 53ch January 1953 2 June 1969 Gloucester (G)
OE1 Oxenholme No 1 Code used from 29 April 1973 CGJ7 c18m 45ch   12 May 1973 Carlisle (CE)
OE2 Oxenholme No 2 Code used from 29 April 1973 CGJ7 c19m 5ch   12 May 1973 Carlisle (CE)
OX Oxford   DCL 63m 46ch 7 October 1973 7 July 2018 (last train);
16 July 2018 (official)
Thames Valley Signalling Centre (OD)
BT Signals protecting Bicester London Road level crossing
DM Down main line automatic signals
DX Down Oxford line automatic signals
OD Code shown on some plans, believed never carried
UM Up main line automatic signals
UX Up Oxford line automatic signals
OR Oxford Road   COL c189m 37ch     Manchester Piccadilly (MP)
OS Oxheys   CGJ6 c1m 30ch   3 February 1973 Preston (PN)
OY Oxley   WSJ2 143m 14ch 30 March 1969 29 November 2010 West Midlands Signalling Centre (OS)
CS Oxley Carriage Shed   WSJ2 c143m 17ch      
O Oxmardyke Gate box: line controlled by Gilberdyke Junction (G) HUL1 16m 22ch 1901 23 November 2018 (last train);
26 November 2018 (official)
(delayed from 3 April 2018)
York Rail Operating Centre (GH)
OX Oxmarsh Crossing   BAR 106m 39ch 1959    
OM Code reported but not seen on site
O Oxspring Junction   PED2 0m 20ch 1933 20 May 1973 Line closed
CCM Oxted Original code phased out 1985-1987 SCU1 20m 32ch? 1896 July 1987? Oxted [new] (OD)
OD New code phased in 1985-1987
OD Oxted [new]   SCU11 20m 32ch 11 July 1987    


Introduction | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Non-National Rail | Ireland | Western region MAS dates | Mechanical signalling bell codes