If you had seen this panel, you would have expected it to be something to do with sewers or the metal door being a panel to an underground box and maybe access to electrical or telephone equipment, you definitely would not think it led to a large underground complex never mind a self-contained Nuclear control bunker.

Behind the thick 'Blast Doors' which formed an airlock, a decontamination corridor led through with rooms on either side. It had a kitchen, toilets, electrical plant room (Generator etc), Offices. Two larger rooms to the right, one with a large semi-circular table facing a large map wall and a very annoying constantly bleeping nuclear alert speaker set high on the wall. It was this room we used for the majority of our theory training sessions as it was suitably equipped to use a projector.

The other large room we used for the more practical training, being almost empty apart from stacks of chairs and a medical examination table. An escape hatch was built into the far wall in the corner. Other rooms were locked and not accessible to us, but from what little we could see through the misty glass were stocked with archive files and communications equipment. one room appeared to be full of plants, whether this was some form of hydroponics, used to produce oxygen and remove nitrogen from the air or just someone growing garden plants we couldn't say, for all we knew it could have been a cannabis factory, not that we knew what Cannabis even looked like!. 

Where the escape hatch emerged we never found out. there was nothing else visible in the dusty un-surfaced car park above unless it was buried or hidden. One of our instructors worked in or at least had something to do with the bunker, (exactly what though we were not privileged or perhaps cleared to have been disclosed), hence us being allowed to access and use it, without saying anything definite he 'hinted' that in an unacessible part behind the locked doorways that led off the main corridor, had further access tunnels to other buildings in the town, one being the Bus Garage and another the old Cinema building (Not the main cinema) further down the Broadway that had been disused for many years and I believe was later made into a small Tesco supermarket.