It became lined with some of the largest privately owned mansions in London , including the Duke of Westminster 's Grosvenor House ( replaced by the Grosvenor House Hotel ) and the Holford family 's Dorchester House ( demolished in 1929 and replaced in 1931 with The Dorchester ) , and the Marquess of Londonderry 's Londonderry House on the corner of the lane and Hertford Street , the site of which is now occupied by the Metropolitan Hotel .
It became lined with some of the largest privately owned mansions in London , including the Duke of Westminster 's Grosvenor House and the Holford family 's Dorchester House ( demolished in 1929 and replaced by 1931 with The Dorchester , which are now both hotels , and the Marquess of Londonderry 's Londonderry House , which has been demolished .