A bunker with an interesting history, part of Southern Railway Control Centre. Unlucky for me it was badly flooded during my visit.
Redhill is one of three divisional control rooms built to regulate the flow of railway traffic on each of the three divisions (South Western, Central and South Eastern) of the Southern Railway, later Southern Region. The controllers would take executive decisions as to which trains have priority, how to allocate scarce resources and so on. In this connection they are provided with dedicated ‘Control’ telephones to every signal cabin in their Division and to other strategic locations (e.g. other control offices, main motive power depots, Electrical Control office, etc.). In more recent times there was also a Control teleprinter network as well. Over and above these Divisional controls there is was also a Regional control, which for the Southern Railway during WW2 was in underground tunnels excavated in the hillside behind Deepdene House near Dorking. Both this regional control centre and the three divisional control centres at Redhill, Orpington and Woking remained operational until the mid 1960’s. Following closure the bunker and the building above it remained empty until the mid 1980’s when British Rail’s permanent way team at Redhill required new premises as their old huts were due for demolition to make way for the new station car park. The brick building on top of the bunker seemed ideal for the purpose. It had housed exchange equipment and all the remaining switching frames and a back up power supply of heavy duty batteries were cleared at this time and new partition walls inserted inside the building. Two of the rooms inside the bunker were also utilised.
Some pics here: