An expensively engineered underground swimming pool with a rising floor is among the features of the Co. Waterford castle bought by Facebook founder Mark Zuckerberg.

The Meta CEO and his wife, Priscilla Chan, are understood to have completed the purchase of Strancally Castle in Knockanore several weeks ago.

It is estimated that Mr Zuckerberg, the seventh–richest person in the world according to Forbes with a net worth of around €162billion, will have paid between €20million and €30million for the gothic castle and 440–acre estate.

Previous owners Michael and Giancarla Alen–Buckley spent the past 25 years renovating the 200–year–old castle, bringing it to its current super–luxury state. 

The works included the addition of a marble staircase which runs up all three floors of the castle, and cost a million euro two decades ago.

And more recently, a high–tech, trap–door–like pool that will have James Bond fans immediately reminiscing of the spy’s close shaves with his nemeses Ernst Blofeld and Emilio Largo – was installed under a patio adjacent to the house, engineered by Co. Cork–based firm Cumnor.

Mark Zuckerberg and his wife Priscilla Chan are understood to have completed the purchase of Strancally Castle in Knockanore, Co. Waterford, several weeks ago

It is estimated that Zuckerberg, the seventh–richest person in the world according to Forbes, will have paid between 20 and 30million euro for the gothic castle and 440–acre estate

A blurb in the firm’s online portfolio describes the project as a ‘striking, below–ground leisure facility seamlessly integrated with a historic castle setting. 

‘It delivered a 25m indoor–outdoor pool with a rising floor that transforms into a terrace, alongside spa, gym and lounge spaces.’

Rising floor pools can be drained at the touch of a button as the base moves up to ground level, providing more floor space.

A blurb in the firm’s online portfolio describes the project as a ‘striking, below–ground leisure facility seamlessly integrated with a historic castle setting…’

‘…It delivered a 25m indoor–outdoor pool with a rising floor that transforms into a terrace (above), alongside spa, gym and lounge spaces’ 

Strancally Castle was built in the late 1820s on the banks of the Blackwater River, on the site of a previous 12th–century Norman castle

Strancally was built in the late 1820s on the banks of the Blackwater River, on the site of a previous 12th–century Norman castle.

It was designed by renowned English architect brothers James and George Richard Pain for John Kiely, a Tory MP for Clonmel and the High Sheriff of Co. Waterford from 1819 to 1820.

It was sold in the 1850s to George Whitelocke Lloyd, and it then remained in his family well into the 20th century.

The mansion changed hands several more times before the Alen–Buckleys acquired it around 2000 and began their extensive two–decade restoration project.

Michael Alen–Buckley is co–founder and chairman of the London–based investment firm RAB Capital.

It was sold in the 1850s to George Whitelocke Lloyd, and it then remained in his family well into the 20th century

‘Unwary’ victims were bound  and then dropped through a trap door into a flooded cave, where their ‘gasping shrieks’ could be herad as they were swept away to their deaths

Giancarla is the daughter of the Italian–Scottish hotelier Charles Forte, of the Forte Group.

It is expected Mr Zuckerberg and his family will continue to live in the US and would use the castle when in Ireland.

The European headquarters of his company Meta, which incorporates Facebook, Instagram and WhatsApp, is in Dublin, around two hours 50 minutes away by car.

A grisly story – one involving yet another Bond–villain–style trap door – also forms part of the castle’s history.

Author William Howitt wrote in his 1894 book Homes and Haunts of the Most Eminent British Poets of a ‘murderous device’ carved into a rock leading to a cave over the Blackwater.

He wrote: ‘The unwary, when decoyed within the castle, were tied hand and foot, and hung down the murder–hole – the rapid river hurried by, and soon carried away their gasping shrieks, and the dead told no tales.’