Finally got round to paying this place a little visit; This used to be part of the body shop areas for a Factory. The shelter is unique about 400ft long, it was constructed out of brick and reinforced concrete; using a cut and cover method with a possibility of mining. It has possibly been used for storage since the war. Sadly the Body shop itself has been demolish over a decade ago… this is all that left.
Unfortunately the place has suffered a fire but that didnt stop me enjoying seeing it
There is an amazing article with more information about this place here http://www.martynlnutland.com/uploads/1/1/8/5/11850066/austin_times_feb_mars_08.pdf