The spacious underground cavern can be accessed from a lone doorway set in the patio terrace belonging to the two-bedroom home in The Laboratory Building in Rosebery Avenue, Clerkenwell.
The entrance to the bunker (Image: Unique Estates Property Services)
The door way to the bunker is set into a grassy mound on the flat's patio terrace (Image: Unique Estates Property Services)
In the 1930s Thames Water scientists had used the former Metropolitan Water Board HQ as a lab to test reservoirs and rivers up and down the country, and when the Second World War broke out underground bunkers were built to house the staff and protect them from booming raids.
Interestingly, the joint owner’s father was worked as a scientist for Thames Water at that time in the Art Deco building, which was converted into flats in the 90s.
The Laboratory Building - the former Metropolitan Water Board HQ in Rosebery Avenue, Clerkenwell (Image: Unique Estates Property Services)
The Laboratory Building - the former Metropolitan Water Board HQ in Rosebery Avenue, Clerkenwell (Image: Unique Estates Property Services)
The current owners have brought the bunker back from dereliction, and made the space usable with a complete refurb, painting the whole thing white.
It was tanked to prevent water ingress, and they installed heating, lighting and its own ventilation system.
The current owners installed a ventilation system into the bunker (Image: Unique Estates Property Services)
One of the joint owners, who wished to remain anonymous, told the Gazette: "When we purchased the property the WWII bunker was derelict .
"There are two bunkers, one of which has direct access from our flat, and the bunkers were connected however we sealed the doors so that we could have independent space from the other flat."
The vast space could be used as a home office or a music room, gym, storage - or could even by seen as desirable by Doomsday preppers (Image: Unique Estates Property Services)
Agents from Unique Estates Property Services, who are marketing the property, suggest the space could be used as a home office or a music room, gym or just storage.
The huge bunker was used by Thames Water scientists during WW2 (Image: Unique Estates Property Services)
Founder and director Chris Georgious said his agency had received lots of responses to the "very unusual" property, and that he "hadn't seen anything like it" in his 18 years in the business.
He said: "It’s huge. It’s completely underground with no windows you can go in and shut the door and you have fresh air in and out.
It’s an interesting one, and there are so many things you can do with it.
"If it was me, I’d put a projector up down there and install a pool table, but I’m sure there are other things that Doomsday preppers might have in mind."
The door way to the bunker is set into a grassy mound on the flat's patio terrace (Image: Unique Estates Property Services)
The bunker can be accessed through a heavy, secure door, after descending underground through a door in the garden (Image: Unique Estates Property Services)
The bunker is accessed from a second secure door, after descending underground through the door in the garden (Image: Unique Estates Property Services)
The huge bunker was used by Thames Water scientists during WW2 (Image: Unique Estates Property Services)
The vast space could be used as a home office or a music room, gym, storage - or could even by seen as desirable by Doomsday preppers (Image: Unique Estates Property Services)
Agents from Unique Estates Property Services, who are marketing the property, suggest the space could be used as a home office or a music room, gym, storage (Image: Unique Estates Property Services)
The bunker's hallway below the two-bedroom flat in The Laboratory Building in Rosebery Avenue, Clerkenwell (Image: Unique Estates Property Services)
The secure door to the bunker beneath The Laboratory Building in Rosebery Avenue, Clerkenwell (Image: Unique Estates Property Services)
The massive bunker lies beneath The Laboratory Building in Rosebery Avenue, Clerkenwell (Image: Unique Estates Property Services)
The huge bunker lies beneath The Laboratory Building in Rosebery Avenue, Clerkenwell (Image: Unique Estates Property Services)
The current owners installed a ventilation system into the bunker (Image: Unique Estates Property Services)
A communal window in the Laboratory Building, former Metropolitan Water Board HQ (Image: Unique Estates Property Services)
The reception room in the two-bedroom flat in The Laboratory Building in Rosebery Avenue, Clerkenwell (Image: Unique Estates Property Services)
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