Doctor Who fans ask: “Is there really a secret underground lake below Sheffield Town Hall?”

It kicked off 2019 in explosive style – and the latest episode of Doctor Who left fans wondering whether there really is a secret underground lake beneath Sheffield Town Hall.

New Year’s Day episode Resolution saw Time Lord Jodie Whittaker investigating the discovery of a Dalek in the bowels of the Town Hall, with characters reacting in horror as a terrifying squid like creature emerged from the pools of water supposedly below the building.

So, is there really a mystery subterranean lake beneath the building that’s a breeding ground for the Doctor’s most feared foe?

Well, sort of.

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While the basement of the Pinstone Street building is distinctly dry, there is a secret underground water cavern in Sheffield.

The Doctor investigates the discovery of a Dalek beneath Sheffield Town Hall. (Photo: BBC).

The Doctor investigates the discovery of a Dalek beneath Sheffield Town Hall. (Photo: BBC).

It is called the Megatron – and many Sheffielders don't realise that every time they walk through the city centre, they are walking on an amazing network of underground water filled tunnels.

The Victorian-engineered subterranean drainage system was built in the mid-1800s below the city centre and boasts an impressive network of cathedral-like brick archways and interconnecting darkened tunnels to contain the overflow of water from a storm.

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The impressive vault-like tunnel system was constructed in an effort to channel the huge flow of water from the three main rivers (Sheaf, Porter and the Don) that run through Sheffield, and contain the overflow following heavy rain.

The Megatron lies beneath Sheffield.

The Megatron lies beneath Sheffield.

The existence of the cavernous underground drain was shrouded in mystery and rumours for many years, with whispers that respiratory equipment was required to enter into its depths due to harmful fumes.

But while The Megatron has long been forgotten by most, it has attracted the eye of extreme sports enthusiasts with Sheffield wakeboarders speeding through the tunnel system.

Tuesday’s episode saw two archaeologists carrying out a dig beneath the Town Hall and discovering a Dalek which had supposedly lain there since the 9th century and left viewers pondering what lies beneath Sheffield.

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Is there really a mystery lake beneath Sheffield Town Hall?

Is there really a mystery lake beneath Sheffield Town Hall?

Joe Oliver tweeted: “Is there really a cool Phantom of the Opera style subterranean lake under Sheffield Town Hall?”

Jeremy Carter added in a tweet: “Never going to look at Sheffield town hall in the same way again!”

Andrew Fellows‏ added: “Daleks lurking under Sheffield Town Hall. Who'd have thought.”

It is not clear if the Megatron was used for filming of the scenes – although other parts of Sheffield including Park Hill were used as locations in the most recent series.

The Town Hall dates opened in 1897 after construction got under way in 1890.

The building was opened by Queen Victoria, using a remote control lock from her carriage. The turning of the key in the lock triggered a light in the building which was the signal for three concealed men to open the gates.

Don't panic, there aren't really Daleks below Sheffield Town Hall. Or are they?

Don't panic, there aren't really Daleks below Sheffield Town Hall. Or are they?