RISC OSMap of G.W. SignalboxesRISC OS
http://www.svrsig.org/gwmap/GWMap.htm
Sxxxx numberSignal Box nameView on map squareOther information including SRS diagram number
S 74 Princes Risborough South Map CL131
SP799026
SRS diagram S786
S 123 Thame Map CE132
SP713052
SRS diagram D511 (1950, 1960)
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