Before the re-imagining of London Bridge station in the 2010’s, it was the subject of a huge re-signaling scheme in the mid 1970’s. The idea was to completely redesign the approach, especially across Borough Market Junction. This was a notorious bottleneck where trains from Charing Cross and Cannon Street, as well as approaching traffic from Kent and Sussex would almost always grind to a halt at peak times.
The solution was to create more throughput by using crossovers from Charing Cross and Cannon Street and using a new flyover at St Johns. Some terminal platforms were also connected to the Charing Cross lines in order to facilitate more throughput.
The entire area would be controlled via a massive new signal control room at London Bridge, which would mean the demise of at least 16 smaller signal boxes nearby.
Amazingly for such a large project, it was finished on time, at a cost of £21.5 million pounds in 1978. Below are some scans from a mini booklet produced by British Rail to commemorate the achievement.
I must thank Mr David Bonnett, who very kindly donated this leaflet and other materials to myself.
Please visit my YouTube channel
Please visit my Facebook page
Please visit my Instagram page
Many thanks for reading, I will blog again soon.
Rainham Rail Enthusiast 
I remember it well, especially the day with Percy Hirst in the observation saloon supposedly looking at the new layout, which was a complete waste of time.
LikeLiked by 1 person