Three-hundred years ago London's wealthiest land-owning families became developers - building on their huge estates and giving shape to the city we know today.
- © Alex Lentati
Many of these families still own large acreages of central London - now covered with valuable commercial and domestic property - showing a remarkable ability to survive turbulent economic cycles.
Here we begin a series looking at these great estates, how they have shaped modern London and are set to fashion its future.
The Duke of Westminster is the richest landlord of them all - and is the wealthiest British-born man in the country - with an estimated £6.5 billion fortune. At the end of 2008, his company, Grosvenor Group, had total assets of £12.6 billion.
Like other London estate owners, he has had to move with the times and take on the challenges of leasehold reform, which has had the greatest impact on ownership history in the lifetime of the estates.
The Grosvenor estate comprises 300 of London's most expensive and prized central-London acres in Belgravia and Mayfair. It has 3,800 properties (10.7 million sq ft). About 2,500 of these are residential long-leasehold homes. The number of rental units - currently 300 - has increased by a third since 2005. Forty nine buildings on the estate are Grade I listed.
More than half the retail portfolio is devoted to community and neighbourhood uses, from pubs to pharmacies, grocers to cobblers - 80 per cent of which are independently owned.
Thanks to some loyal service by his forebears to William the Conqueror, and a strategic programme for marriages in the 17th century, Gerald Cavendish Grosvenor, 6th Duke of Westminster, is now landlord to famous department store Harvey Nichols, more than 300 embassies and hundreds of London's most exclusive addresses.
The family's Mayfair estate was completed in the 1780s and consisted of a grid of gracious, wide streets, with Grosvenor Square in the centre, surrounded by mansions.
Much redevelopment was carried out in the 19th and early 20th centuries, and only a few of the original buildings remain, the oldest being Bourdon House on Davies Street.
BE HERE, BE SEEN
Many of Mayfair's wealthy families fled London during the Blitz and never returned after the Second World War. So grand houses were converted into offices. Grosvenor had anticipated the rising demand for business space in the post-war period, and had begun to grant "temporary" (50-year) office leases. In the Nineties, as these leases expired and hedge fund managers and other entrepreneurs targeted Mayfair as a place to live as well as work, Grosvenor initiated a programme of residential reversions.
About 250 buildings have since reverted to residential use and the process is continuing. Several mansions have been reinstated as homes, while Grosvenor has collaborated with niche developers to create large lateral flats or transform modest mews houses into spectacular homes.
New apartments have been built above the Cipriani restaurant opposite Claridges, while a site has been cleared for the area's biggest residential project in decades: 39 flats at the Park House retail development on Oxford Street.
At revitalised Mount Street, where the Connaught Hotel, Scott's restaurant and fashion boutiques, such as Balenciaga, attract celebrities, retail rents are now among the highest in the world.
Grosvenor has a wider strategy to acquire buildings that it sold off generations ago and to cultivate new neighbourhood hubs.
Another improving Mayfair pocket is the area around Duke Street. Brown Hart Gardens is one of the capital's secrets - a raised public space built above an electricity sub-station and enclosed by Italianate stone pillars and domes.
Starting soon on Duke Street is a refurbishment of listed buildings that will create 16 lateral apartments and retail units. This section of Mayfair, on the Oxford Street fringe, is currently the lowest-value part of the estate.
Grosvenor's aim is to keep major commercial buildings to the busy traffic routes at the edges of the estate, while protecting the more sheltered environment within.
Belgravia has fewer commercial buildings than Mayfair and is seen as a more convivial neighbourhood for families and year-round residents, which is why it is 10 per cent dearer.
Grosvenor first developed the area at the end of the Napoleonic Wars and it became more fashionable after the conversion of Buckingham House into a palace for George IV in 1826.
Regency-style squares, streets and crescents overlook private gardens surrounded by unified palazzo façades. Eaton Square is regarded as the jewel in the crown but the patch between Lowndes Square, where Roman Abramovich is converting two town houses into a mega mansion, and Belgrave Square, is an increasingly prized address.
A MAYFAIR HOME FOR £300,000
Grosvenor recently introduced to Mayfair a 20-year residential short lease that it has been using successfully in Eaton Square, Belgravia, since the sixties. Leases of this duration fall outside enfranchisement laws, meaning leaseholders cannot extend their lease or buy the freehold, allowing Grosvenor to keep control of its property assets.
But these cheaper leases suit certain buyers, including downsizers and entrepreneurs who do not want to tie up all their capital, says John Clark, Grosvenor's residential investment director. Currently, 20-year lease flats are available in Brook Mews, Davies Street and Park Street, priced from £300,000 to £450,000. Grosvenor offers a "pledge", undertaking to top-up the lease to the original 20-year term at any point during the lease. The price leaseholders pay reflects the difference in value between the existing lease and the new lease, as set by an independent surveyor.
Grosvenor also offers rental properties in Mayfair and is collaborating with celebrity designers to create what it calls "statement apartments", such as the three-bedroom duplex on Dunraven Street. The 3,600 sq ft interior by Ben de Lisi is "inspired by Fifties glamour". The rent is £3,500 per week.
Grosvenor and niche developers have created lateral flats and turned mews houses into spectacular homes.