There are places like this, a bit bigger though. In the event of a nuclear holocaust they were to be used by local government people and the great and the good, to run the country. They are situated all over the country and some are now being sold off because they are outdated. Inside were dorms, comms centres, kitchens, rec rooms, the whole shebang. I did a comms exercise in one in the 1960's, not on the Wirral I might add. They were billed as Ministry of Works Depots for local consumption.
Birkenhead........ God's own Room 101.