London

Land at Heathrow and take the Elizabeth Line or a black cab into the city — the first glimpse of the Thames, the terraced Georgian streets, and the red double-decker buses produces the specific happy disorientation that London induces in first-time visitors. Check in, freshen up, and immediately go walking — London rewards curiosity more than any agenda. If you're staying near the river, walk the South Bank from the London Eye past the Tate Modern to Tower Bridge as the city lights come on; if you're in Mayfair or Covent Garden, wander the lamplit streets toward Soho for dinner. Tonight: a low-key gastropub dinner and an early night.

Begin at Westminster Abbey — 1,000 years of coronations, royal weddings (William and Kate were married here in 2011), and the tombs of everyone from Elizabeth I to Isaac Newton. Book the first entry slot of the day to beat the crowds, then walk up through Parliament Square past Big Ben and the Houses of Parliament, along Birdcage Walk through St James's Park (the prettiest of the royal parks), to Buckingham Palace for the Changing of the Guard at 11 AM (check dates — it doesn't run daily). After lunch, stroll through St James's — London's most aristocratic neighborhood, home to gentlemen's clubs, Jermyn Street shirtmakers, and the oldest cheese shop in England — then back through Green Park to your hotel to freshen up before dinner.

Take the Tube to Tower Hill and arrive at the Tower of London for opening — the Crown Jewels are best seen in the first hour before the tour groups arrive, and the Yeoman Warder ('Beefeater') tours that run every 30 minutes are among the best guided experiences in any city: 1,000 years of executions, imprisonments, ravens, and royal intrigue delivered with genuine theatrical flair. From the Tower, walk across Tower Bridge (the high-level glass-floor walkway is worth the small ticket price), then turn west and walk the South Bank — Shakespeare's Globe, the Tate Modern (free, and the Turbine Hall always has something extraordinary), Borough Market for lunch (go hungry — this is London's greatest food market), and end your walk at the London Eye for your private sunset capsule. Dinner tonight in a candlelit converted church or one of the riverside restaurants along the South Bank.

The British Museum is the single greatest museum of human civilization on the planet — and it's completely free. Three hours here can cover the Rosetta Stone, the Parthenon sculptures, the Egyptian mummies, the Lewis Chessmen, and the Sutton Hoo treasure; a private guide (worth the modest cost) turns what could be an overwhelming maze into an intimate encounter with the greatest things humans have ever made. Walk south through Bloomsbury into Covent Garden for lunch and street performers, browse Neal's Yard and Seven Dials, then return to the hotel to dress for the theatre. Tonight: your West End show — the guide includes our picks, from long-running musicals to the latest serious drama at the National or the Donmar.

Take the train from Paddington (30 minutes, Windsor & Eton Central) to Windsor — the oldest and largest inhabited castle in the world, a working royal residence for 1,000 years. The State Apartments are breathtaking, St George's Chapel is where Harry and Meghan were married and where Elizabeth II is buried, and Queen Mary's Dolls' House is a miniature palace with working plumbing and electricity that delights everyone who sees it. After the castle, walk across the bridge to Eton — the famous school's chapel and the high street's tailors (where boys still get measured for their tailcoats) are genuinely fascinating. Return to London by late afternoon for your afternoon tea reservation — the one non-negotiable splurge of the trip, scones and clotted cream and finger sandwiches and champagne in a chandeliered hotel lounge.

Saturday in London means Portobello Road Market — the world's most famous antiques market fills Notting Hill's most photographed street, flanked by the pastel-painted houses that have made the neighborhood Instagram's favorite corner of the city. Arrive early (before 9 AM) for the best finds and the emptiest streets, then walk the market end-to-end before the crowds. After lunch, stroll through Holland Park (the Kyoto Garden is the most romantic corner of any London park) and into Kensington Gardens — Kensington Palace, where Victoria was born and where a new generation of royals now lives, the Italian Gardens, and the Serpentine, where you can rent a rowboat for the classic honeymoon photo. End with a sunset drink on a rooftop back in the city and a final celebratory dinner.

A final London morning is best spent slowly. If you're a reader, make a pilgrimage to Daunt Books in Marylebone — the Edwardian oak-galleried travel bookshop is one of the most beautiful rooms in the city — or to Hatchards on Piccadilly, the oldest bookshop in London. Pick up a final box of Fortnum & Mason biscuits and a proper tin of tea for the flight home, take one last walk through whichever royal park is closest to your hotel, and sit for a while on a bench with the squirrels and the office workers and the specific melancholy that London always induces on departure. Heathrow via the Elizabeth Line; a window seat on the right side of the plane will give you a last view of the Thames and the city receding below.