She's the wealthiest woman in British and Irish music with a fortune of £91 million - which even beats chart-topper Adele.

But Enya, 54, has maintained a reclusive existence since she shot to super-stardom following the release of her global hit Orinoco Flow (Sail Away) in 1988, and has never toured her solo material.

A friend of the secretive singer even recently told The Sun: 'She’s not exactly a barrel of laughs. You wouldn’t go for a few pints with her.'

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Success story: Enya, 54, is the wealthiest woman in British and Irish music with a fortune of £91 million

While her uncle Noel Duggan admitted: 'We don’t see much of her. She lives like a queen. She is a recluse.'

Enya, who is renowned for her ethereal vocals, lives in the impressive Ayesha Castle in Killiney, south Dublin, which boasts stunning views of the Irish Sea.

She purchased the building for £2.5 million in 1997 and currently lives alone with only her cats for company.

Her next door neighbour is U2 frontman Bono and in a rare televised appearance on This Morning last month she joked that the rocker popped round to borrow sugar.

Doing it her way: Enya, 54, has maintained a reclusive existence since she shot to super-stardom following the release of her global hit Orinoco Flow (Sail Away) in 1988, and has never toured her solo material

She previously told The Guardian: 'It's very castle on the exterior, but it's very much a home inside. It's actually a very small castle and I fell in love with it'

Her unique brand of music is created in collaboration with producer Nicky Ryan, 67, and his lyricist wife Roma.

The Irish songstress is her country's best-selling solo artist and has released nine studio albums, selling an estimated 75 million records worldwide.

She's recorded in 10 different languages including in Lord of the Rings creator JRR Tolkien's Sindarin and Quenya, as well as a language created by herself and her songwriters called Loxian.

The star's success is an anomaly in an industry where constant touring, heavy radio play and public appearances are usually required to return strong record sales.

An industry insider told The Sun: 'Throughout the music business there’s no one else who is so successful about whom so little is known. She doesn’t socialise, she’s barely seen out of the house, there aren’t any clues in her lyrics about her life.'

However, she has vehemently defended her lifestyle and approach to music.

Impressive! The Irish songstress is her country's best-selling solo artist and has released nine studio albums selling an estimated 75 million records worldwide

'It's not a hanging offence not wanting to go to nightclubs,' said the singer. 'What happened to choice? My choice is that after a certain amount of promotion, I feel it gets very false and then I'm not interested.

'When the album has been out for, say, 10 months, people will start focusing on me and I really don't want that. I love the music to be known, but I'm not after fame for myself.'

She told The Independent that she had 'never tried to create an enigma' but has always been an independent person.

While she longs to create unique music uninfluenced by current chart trends, she allegedly has an eclectic taste in music which includes Green Day and Puff Daddy.

Her passion for music has had an impact on her love-life, although music is what's most important to her.

She previously said: '...there have been… relationships. It's quite hard to have someone accept that – well, not that they are second to the music, but that I do need a certain amount of space for it. And even though the person will understand that at the beginning, there is something like jealousy towards the music after a while.'

Hailing from a musical family, Enya became a member of the Celtic folk band Clannad in 1980 but left just two years later to pursue a solo career.

Unique: The star's success is an anomaly in an industry where constant touring, heavy radio play and public appearances are usually required to return strong record sales

While each of her records through the nineties sold well, she had a boost in sales following the 9/11 terror attacks when her song Only Time, from her album A Day Without Rain (2000), was used by CNN to accompany clips of shocking footage from the attacks.

Her distinguished career has seen her win four Grammy awards as well as an Oscar nomination and Golden Globe gong for May It Be, a song she wrote for Lord of the Ring: The Fellowship of the Ring.

Last year, she released her eighth album which peaked at number 4 in the UK album charts, her highest charting album since 1991.

Explaining why Enya has managed to beat second-placed Adele to the top spot, despite the phenomenal success the Tottenham-born mother-of one has achieved by the age of 27, Ian Coxton, who has edited the rich list for 20 years, said: ‘She’s consistent with her wealth... we’re looking at wealth going over a number of years.

'Enya hasn’t moved a great deal, she’s only up a million this year but she’s a well-established artist and over her career has sold millions of records. Once you’ve got the wealth you staying the list, it doesn’t disappear.

'She’s still performing and still producing records, and a lot of these established artists, their followers go out and buy their records so that’s a guarantee of some income in royalties.'