A secret no longer, as it has been featured in the local press and even opened its unassuming door (behind the yellow railings) to visitors during Heritage Open Days.
Concealed beneath the former Castle Court offices on the Shire Hall site and covered by a living roof, the bunker would have provided a safe refuge for council officers to coordinate responses to any nuclear incident affecting the area.
Protected by an airlock and two blast doors, it provides working space and living accommodation for up to 40 personnel. There is a communications suite to enable enquiries from the public to be answered and information and advice to be broadcast to the local population. It has its own independent power supply and reserves of fuel and water to permit it to operate off grid.
Over the years the facility has been used not only for civil defence training exercises but as a call centre in response to local flooding and other emergency incidents. It now provides archive storage for the County Council's archaeology unit.
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