Manchester town hall has been keeping secrets.

That might seem blindingly obvious – given the nature of politics – but these secrets are different; they are hidden morsels of history being unearthed from the Victorian landmark’s bowels, where they have sat gathering dust for generations.

Whole areas of the extraordinary building have been hidden from visitors and tour groups, some rooms rarely entered or even remembered by current council officials.

But ever since experts started a survey of the building to see what work needed doing to preserve it, they have been tripping over long-forgotten treasures.

Nowhere more so than in the basement warren which was used as the town hall’s air raid shelters during World War Two.

(Image: Vincent Cole)

Behind a small door still bearing a slightly eerie sign reading ‘CONTROL. No admittance except for control staffs’ – a sign pre-dating any current staff – is an extensive network of cellar rooms that in the 1940s were reinforced with corrugated metal ceilings and extra internal walls.

It doesn’t feature on tours, but at one time hundreds of council staff and politicians would have hidden there in fear of their lives.

The air raid shelter has two brick toilet cubicles, a reminder of its past life, evidence of the practicalities of long, boring hours spent by officials waiting for the sirens to stop.

(Image: Vincent Cole)

But after the war life moved on and like so many other air raid shelters across the city – next door Central Library had one in its basement, too – it was swiftly given new uses.

In the years that followed 1945, generations of council officers found it a handy place to squirrel away records and folders that might one day be needed, or at some point in the future could be disposed of.

Those officers would move on to be replaced by new officers following the same processes, leaving drawers and files and rooms full of history to accumulate, unremembered.

(Image: Vincent Cole) (Image: Vincent Cole)

So when heritage experts delved into the network of little basement rooms, they found a treasure trove.

One still contains what could easily be a mini museum of 20th Century civic government.

A bizarre jumble of different filing cabinets sit alongside each other: lining the walls are modern box files, next to a 1930s filing bureau with each drawer labelled from 1933 onwards up until 1942. On the side is a folder marked ‘1994’ next to a typwriter-like contraption dating back much, much longer.

Still piled up in another part of the former shelter are burgundy leather-bound tomes of annual general rates dating back to the 1950s and beyond.

Then there are the lord mayor’s records.

In one room archivists found an extraordinary haul of ceremonial photographs and documents dating back nearly 100 years, now being carefully sifted through by experts at Central Library.

(Image: Vincent Cole)

(Image: Vincent Cole)

Among them are images of Harold Wilson unveiling the Mancunian Way in 1967, visits from George VI and an appearance by the pre-war American president Woodrow Wilson.

There is a whole file dedicated just to the evening, again in 1967, when Sir Matt Busby was given the freedom of the city, complete with table plans, guest lists and even a menu.

See Harold Wilson opening the Mancunian Way:

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(The menu is an ode to fashionable 1970s dining, written all in French for no discernible reason, featuring lobster vol-au-vents, smoked salmon and quiche lorraine.)

The position of lord mayor is a treasure trove in itself, and not only thanks to the reams of records languishing in the town hall basement.

Mostly unseen by the public, the lord mayor’s private quarters are a relic of an era in which the position really was Manchester’s answer to royalty, before politicians decided such splendour was unwarranted.

On the second floor, near to the main council chamber, is a doorway whose original glass is still etched with ‘The Lord Mayor Private’.

(Image: Vincent Cole)

Behind it a staircase – carpeted in original fleur-de-lis crimson – leads downwards to a private entrance onto Princess Street, no longer open but historically only used by the lord mayor and guests, from kings and queens to cabinet ministers and foreign presidents.

In a little cubby-hole near the door would once have sat a personal gatekeeper, while a separate antiquated lift – now mainly used for catering purposes – ferried high-profile visitors up and down.

Original gas lamps, now converted to electricity, light the staircase.

Here, too, there have been treasures uncovered. In a cupboard surveyors found a collection of green enamel hot water urns, thought to have been used by successive lord mayors for afternoon tea with the queen and dignitaries.

At the top, the sweeping staircase opens onto the lord mayor’s parlour, complete with a huge portrait of Queen Elizabeth, an original Lowry lent by the Professional Footballers Association and an array of gifts from visitors across the globe – from a hat once worn by Corrie character Minnie Caldwell to a giant bell donated by the Chinese in the 1970s.

Tucked away at one end a selection of now slightly un-glamorous rooms would once have been the lord mayor’s living and guest quarters, where royalty laid their heads.

That came to an abrupt halt in 1984 when the new Labour leadership took exception to the lord mayor’s lavish lifestyle and scrapped much of his perks and entourage.

(Image: Vincent Cole)

From then on the council’s ceremonial figurehead slept at home and the rooms became instead a bolt-hole for Labour politicians to plan their left-wing 1980s campaigns.

The town hall’s secrets from at least the last 150 years are gradually emerging into the daylight.

The treasure being unearthed will all be assessed and archived with the hope that some will soon be displayed for everyone to enjoy in a civic museum.

Inside the 'hidden' parts of the town hall