The Duke's property wealth measured at £9.35 billion made him one of the richest people in the UK.
At the heart of the family fortune is a property portfolio which includes 300 acres in two of London's most expensive neighbourhoods, Mayfair and Belgravia.
The duke recently let his godson borrow his Cessna plane, which is worth £8 million ($10 million), so he could take his wife, the Duchess of Cambridge, and their children - three-year-old Prince George and Princess Charlotte, 15-months - on holiday to the South of France.
The peer nonetheless took seriously his responsibilities to oversee the vast family estate, which includes an art collection, large chunks of Mayfair and Belgravia as well as property overseas and elsewhere in the United Kingdom, including the family seat of Eaton Hall in Cheshire.
The Grosvenor Estate said the 64-year-old duke died Tuesday at a hospital in Preston, in northwestern England, after suddenly becoming ill at his vast Abbeystead Estate nearby.
The sudden and tragic death of The Duke of Westminster, Gerald Cavendish Grosvenor is indicative of the fact that his entire estate, including the family seat in Cheshire, Eaton Hall, will be inherited by his son Huge.
As a child he attended a local state primary school on The Wirral, close to the family home, and then private day school, Mostyn House before attending the co-ed Ellesmere College in Shropshire.
Grosvenor studied countryside management at Newcastle University.
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The 19-year-old has won the last 14 all-around meets she has entered - including three and four USA national championships. The silver is her fifth Olympic medal overall. "I feel like I did my job tonight".
The Duke of Westminster with the Duchess of Westminster.
It was there at his 21st birthday party in January 2012 that comedian Michael McIntyre and the hip hop duo Rizzle Kicks provided the entertainment and Prince Harry was among the guests. The dress code was "black tie and neon".
"Given the choice, I would rather not have been born wealthy, but I never think of giving it up", he told The Independent newspaper in 1992.
Photo of Hugh Grosvenor leaving the christening of his godson, Prince George. That's thanks to a fortunate marriage three centuries ago, which got the Grosvenors 500 acres of land that the family would develop in the early 18th and 19th centuries, thereby getting in on the ground floor of the very fancy West End.