Belgravia, SW1X and SW1W: an introduction made quietly

Three squares, the lanes behind them, and two streets that trade

The district was drawn as one commission for a single landlord, and it has never been allowed to drift since. That is the reason the eye finds nothing to catch on here: one shade of render along an entire terrace, railings at one height, the garden gates locked to one key. Belgrave Square is the state room of the three, with flags over most of its porticoes. Eaton Square carries traffic down its middle and feels the more inhabited for it. Chester Square, the shortest, is the one our companions mention unprompted, usually in the last fortnight of October when the leaves come down on the pale stucco.

Set behind all three are the old stable lanes, cobbled, narrow and now some of the least visible houses in the city. Two streets do the district's shopping. On Elizabeth Street the morning belongs to a bakery and the evening to a handful of tables under awnings. On Motcomb Street the galleries stay lit long after the offices along Grosvenor Place have gone dark, and the Pantechnicon keeps its upper floors busy well into the night.

None of that adds up to nightlife, and the residents would be dismayed if it did. An evening here is held indoors, at a table for two or behind a front door, and the pavement outside registers none of it. For a particular kind of guest that silence is the entire attraction, and it is why this postcode returns to the day book week after week.

Hotels on the border, houses in the middle

The grand houses sit around the edges of the district. SW1X 7HJ faces the Wellington Arch and is the newest of them by a long way. SW1X 7TA keeps its Regency portico at Hyde Park Corner and a butler on every floor. SW1X 7RL stands just over the line into Knightsbridge on Wilton Place. SW1W 0JW is still run by the family who opened it and looks onto its own garden.

Two more share a single address at SW1W 0PS, opposite the long wall of the Royal Mews. One occupies most of the building, while the other keeps the upper floors, small and very private indeed.

Not one of those houses is connected to this one, and no hotel in London has any standing with us. Your companion arrives as your guest and nothing about her arrival announces otherwise. That said, most Belgravia bookings are not hotels: a house on one of the squares, a lateral flat behind a porter's desk, a mews cottage down a cobbled lane. Delphine treats all three identically.

Four stations, and the reason she uses none of them

Victoria, with three Tube lines and the main line concourse above them, is about 5 minutes on foot from the middle of the district. Sloane Square, on the Circle and District lines, is roughly 6 minutes from the western squares. Hyde Park Corner, Piccadilly line, lies some 7 minutes from Belgrave Square, and Knightsbridge about 8 from Wilton Crescent.

Useful for you, irrelevant to her. A companion comes to Belgravia by car and is set down at the number you gave, and since the whole district is central her journey is already inside the fee. Nothing is added on arrival, and the figure she is given is the one Delphine wrote to you earlier in the day.

Because three women live among these squares, the interval between a confirmation and a knock is usually short here. If you would rather fix a later hour, fix it: this house would far sooner arrive at nine precisely than at some point after eight.

Residents, and guests who wish they were

A large share of the messages Delphine receives from SW1X and SW1W come from people who live here, or who have taken a house for a season and would rather host at home than go anywhere at all. Those bookings tend to be long and to repeat, and several have settled into a standing hour on the same evening of the month.

The rest are guests at the border hotels, often in town for a wedding, a sale at the auction rooms or a board meeting that ends late. Both groups ask for the same thing in the end: somebody composed enough to be introduced to a porter without a flicker, and interesting enough to sit with for three hours afterwards.

Three who call these squares home

Lea rarely leaves Belgravia after dark and keeps a small upstairs room on Elizabeth Street as her own. Patricia is exacting, funny about being exacting, and takes a serious evening down a mews off Kinnerton Street. Violetta prefers an open kitchen and a bright dining room on Motcomb Street, then the walk up to Lowndes Square where the stucco is lit from below.

Lucy and Roxi are ten minutes south in Pimlico, and the Knightsbridge women are a short ride across Sloane Street. Everyone else in the Salon attends on the same terms, since proximity shortens a journey and changes nothing else.

Reading outward from the squares

West across Sloane Street, the Knightsbridge park strip swaps silence for shop windows and hotel lobbies. South west, at the foot of that street, the small hotels of Sloane Square mark where Chelsea begins. And because this district shares a postcode with a good deal else, the whole of the SW1 ground is worth reading if your address begins that way. Victoria lies immediately east behind the Palace wall, with Pimlico below it towards the river.