Grosvenor House
Coordinates: 51°30′35.2″N 0°9′19.7″W / 51.509778°N 0.155472°W
Grosvenor House was one of the largest private townhouses situated on Park Lane in London. The house was the home of the Grosvenor family (better known as the Dukes of Westminster) for more than a century. Their original London dwelling was on Millbank but, after the family had developed their Mayfair estates, they moved to Park Lane to build a house worthy of their wealth, status and influence in the 19th century.
The site was occupied by a small house named 'Gloucester House' (after Prince William Henry, Duke of Gloucester and Edinburgh (d. 1805) who owned it) with the front entrance on Upper Grosvenor Street. This house was purchased by Robert Grosvenor, 1st Marquess of Westminster (d. 1845) in 1805 for £20,000. He spent £17,000 on extending the house to make it more fashionable with the times. In 1821, a large picture gallery 50 feet (15 m) long was added to the west of the house. It was in here that many of the Grosvenor treasures were held.
Another extension was added in 1842, in the form of a 110 feet (34 m) long classical-style colonnaded entrance screen on Upper Grosvenor Street. At each end was a triumphal arch with pediments above sculpted with the Grosvenor arms. Thomas Cundy, the architect of this vast house then proposed a larger mansion to go all the way along to Park Street extending all the way to 230 feet (70 m). This was dropped as the 2nd Marquess thought it was to be too lavish.
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