What to do in London: 18 must-sees, from Westminster to Greenwich

The Palace of Westminster, on the banks of the Thames, houses the two chambers of the British Parliament, the House of Commons and the House of Lords. The current Gothic Revival building was rebuilt in the 19th century after the fire of 1834; only Westminster Hall, from the 11th century, survived.

Big Ben originally refers to the great bell of the clock tower, renamed the Elizabeth Tower in 2012. A guided tour of the tower takes you up its 334 steps to the belfry and past the clock mechanism.

A fortress founded by William the Conqueror after 1066, the Tower of London has served in turn as a royal residence, prison, armoury and mint. At its centre stands the White Tower, a Norman keep begun around 1078. Anne Boleyn was executed here, and the future Elizabeth I was imprisoned here.

The Tower holds the Crown Jewels, used at coronations, and its guardians, the Yeomen Warders or "Beefeaters", lead guided tours inside the walls. The site has been a UNESCO World Heritage Site since 1988.

Founded in 1753, the British Museum in Bloomsbury holds around eight million objects spanning human history. Robert Smirke's neoclassical building surrounds the Great Court, covered by a glass roof since 2000.

Among the most visited pieces are the Rosetta Stone, the Parthenon sculptures, the Egyptian mummies and the Anglo-Saxon Sutton Hoo treasure. Entry is free; only temporary exhibitions are paid.

Buckingham Palace is the monarch's official London residence and the setting for state receptions. Its State Rooms can only be visited in summer, from mid-July to late September (dates announced each year on rct.uk).

The Changing of the Guard takes place in front of the palace: the new guard, in red tunics and bearskin caps, takes over from the old guard to the sound of a band. The ceremony is free but does not happen every day: the official Household Division calendar sets the dates.

Westminster Abbey has hosted coronations since that of William the Conqueror in 1066. The present Gothic church was begun in 1245 under Henry III; the Henry VII Chapel, added in the 16th century, has a fan-vaulted ceiling.

More than three thousand people are buried or commemorated here, including many monarchs and, in Poets' Corner, writers and poets. The Abbey has also hosted royal weddings, including that of Prince William and Catherine Middleton in 2011.

Built from 1886 to 1894 to designs by the architect Horace Jones and the engineer John Wolfe Barry, Tower Bridge is a bascule bridge whose two decks lift to let ships through. Its two Gothic Revival towers are linked high up by walkways.

The paid Tower Bridge Exhibition gives access to the walkways, part of which have glass floors above the Thames, and to the Victorian engine rooms that once powered the bridge by steam.

Founded in 1824 and housed on Trafalgar Square in a building by William Wilkins, the National Gallery holds more than 2,300 European paintings, from the 13th century to 1900.

Highlights include Van Gogh's Sunflowers, Van Eyck's Arnolfini Portrait, Leonardo da Vinci's Virgin of the Rocks and works by Turner, Vermeer, Rembrandt and Monet. Entry to the collection is free.

Opened for the year 2000 on the south bank of the Thames, opposite Parliament, this 135 m observation wheel has 32 glass capsules. A full rotation takes about 30 minutes.

On a clear day, the view takes in Westminster, St Paul's Cathedral, the Shard and the City.

Opened in 2000 in the former Bankside power station, designed by Giles Gilbert Scott and converted by the architects Herzog & de Meuron, Tate Modern shows international modern and contemporary art.

The vast Turbine Hall hosts commissioned installations, and the Blavatnik Building extension, opened in 2016, has a viewing terrace on its tenth floor. The pedestrian Millennium Bridge links the museum to St Paul's Cathedral.

The Warner Bros. Studio Tour London, at Leavesden, north-west of London, occupies the studios where the eight Harry Potter films were shot. The self-guided visit takes in the Great Hall of Hogwarts, Diagon Alley, Platform 9 ¾ with the Hogwarts Express locomotive, and costume and special-effects workshops.

Seasonal sets are added at the end of the year and for Halloween. Allow half a day on site.

Covering 142 hectares, Hyde Park is one of London's eight Royal Parks. The Serpentine lake runs through it, next to the Diana, Princess of Wales Memorial Fountain.

In the north-east corner, Speakers' Corner has been a place of free speech since the 19th century, especially on Sunday mornings. The park also hosts large concerts in summer.

In the heart of the West End, Soho is packed with restaurants, bars, jazz clubs such as Ronnie Scott's and small theatres. Carnaby Street, a pedestrian street associated with 1960s fashion, marks its western edge.

To the south, Chinatown and Leicester Square lead on to Covent Garden and the big theatres of Shaftesbury Avenue.

East of the centre, Maritime Greenwich is a UNESCO World Heritage Site. The Royal Park climbs to the Royal Observatory, where the Greenwich meridian runs; below stand the Old Royal Naval College, the National Maritime Museum and the Cutty Sark clipper.

From the General Wolfe statue at the top of the park, the view takes in the towers of Canary Wharf and the City.

North of the centre, Camden Town is known for its markets set around the Regent's Canal lock, in former warehouses and stables: vintage clothing, crafts and world-food stalls.

The area remains a live-music hub, notably with the Roundhouse, a former railway engine shed turned venue. The canal towpath leads on foot towards Little Venice or King's Cross.

West of London, Windsor Castle, founded in the 11th century by William the Conqueror, is the oldest and largest occupied castle in the world. The visit takes in the State Apartments, filled with works from the Royal Collection (Holbein, Rubens, Van Dyck).

St George's Chapel, a Gothic masterpiece, holds the tombs of several monarchs, including Henry VIII and Charles I; it is closed to visitors on Sundays, for worship. Allow two and a half to three hours on site.

West of the centre, Notting Hill is known for its streets of painted houses and for Portobello Road market, whose antique and bric-a-brac dealers set up mainly on Saturdays.

Notting Hill Carnival, a celebration of Caribbean culture, parades every year over the late-August bank holiday weekend. The area gave its name to the 1999 film with Hugh Grant and Julia Roberts.

Between Westminster and Greenwich, the Thames flows past Parliament, the London Eye, Tate Modern, St Paul's Cathedral, the Shard and the Tower of London, and under Tower Bridge. Sightseeing cruises with commentary leave notably from Westminster and Tower piers.

The scheduled Uber Boat by Thames Clippers service also calls at central piers as far as Greenwich and beyond, and can be paid with a contactless card or an Oyster.

Fish and chips, fried cod or haddock with thick-cut chips, is eaten everywhere; the Sunday roast, roast meat with Yorkshire pudding and gravy, is served in pubs on Sundays. Afternoon tea combines tea, sandwiches, scones with cream and jam, and small cakes.

Borough Market, near London Bridge, is the city's great food market, and London has restaurants of every world cuisine, from Brick Lane to Chinatown.