What goes on under the floors of Guildford Cathedral?

Guildford Cathedral, which has stood proudly on Stag Hill since 1961, is an impressive structure.

But that is only half the story because below the serenity of the public parts of the building is a world of tunnels, crypts and sealed rooms not accessible to the average visitor.

Current Guildford Cathedral Architect, John Bailey, who knows every inch of the building which was constructed in four phases, said: "The cathedral is founded on 778 piles which were driven into the hill. It took about 11 months to put all those foundations in.

"If they hadn't put them in in one go, the cathedral would never have been completed," he told Secret Surrey.

While the cathedral took approaching 30 years to complete "in at least four phases", it is a building of real structural integrity, Bailey said.

"Attached to those piles [foundations] is about 5,500 tonnes of concrete and about 700 tonnes of steelwork, so the cathedral's not going anywhere."

That robustness extends to what is beneath the cathedral itself, which includes the original strongroom which is where the "town valuables and items of significance were stored" during World War Two.

Bailey says this room, which held the town clock during this period, remains incredibly secure.

"You need two keys to be able to unlock it.

"[The strongroom] has actually an important part in the history of Guildford," he added.

Because this site required substantial foundations, there is a long service tunnel running almost the full length of the nave, which sits alongside a series of crypt areas.

These crypt areas sit beneath the Lady Chapel, and served as the main worship space from 1947 until the cathedral was completed and consecrated in 1961.

"It's now the choir school," Bailey added.

There is one point underneath the cathedral itself where a person can stop and see the entirety of the site, which Bailey says is "probably 250ft long".

"Running through it are all the main heating supply pipes, all the secondary pipes, and the main electrical cables," he said.

Alongside this he estimates that there are "probably 20 or 30 miles of pipework".

"You can actually walk the entire length of the cathedral down a passage that runs through the nave," Bailey says.

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