What's a good 3-day itinerary for London?

Start at Westminster Abbey at 9:30am — the vergers are still setting up, the nave is cool and quiet, and you'll beat the coach groups by a full hour. Walk along the Embankment past Parliament. Big Ben photographs better from the south side of Westminster Bridge, where you get the full clock face against the sky. Cross to the South Bank and follow the river east to Borough Market, arriving around noon. The pulled pork at Roast is fine, but the queue at Padella for fresh pasta is the one worth joining — fifteen minutes on a weekday, forty on Saturday. Walk it off along the Bankside to Tate Modern by 2pm. The Turbine Hall is free and the sheer height of it still catches you off guard, even on a return visit. Cross the Millennium Bridge to St Paul's Cathedral by 4pm, wander the nave and the churchyard, and stay for 5pm evensong — free, no ticket, and the choir under that dome is the best free concert in the city. Dinner at Anchor & Hope near Waterloo, a gastropub that doesn't take reservations. Just turn up.

Book your Tower of London ticket online for 9am — the Crown Jewels queue builds fast after 10:30, and you want time with the Beefeaters before they start cycling through the same stories for the fifth group. Allow two full hours. Walk across Tower Bridge afterward. The glass floor wobbles slightly underfoot, which is half the fun. Grab lunch at St Katharine Docks — Dickens Inn sits in a converted timber warehouse with a terrace right on the water. Tube from Tower Hill to Russell Square, one change, puts you five minutes from the British Museum. Go straight to the Rosetta Stone and the Egyptian galleries, then the Elgin Marbles — you can cover the essential rooms in a single afternoon if you resist reading every placard. The museum closes at 5:30, except Fridays when it runs until 8:30pm. Walk southwest fifteen minutes to Soho for the evening. Bao on Lexington Street does Taiwanese steamed buns at about £5 each. They're small. Order three.

Day 3 slows the pace. The V&A opens at 10am in South Kensington — the Cast Courts alone are worth the trip, two storeys of plaster replicas of things like Trajan's Column split in half to fit the ceiling. Free entry. Walk northwest through Hyde Park, past the Serpentine and into Kensington Gardens. The Italian Gardens at the Lancaster Gate end are quieter than the Diana Memorial Fountain and, frankly, more interesting. Portobello Road Market runs properly on Saturdays only — if your third day falls midweek, skip Notting Hill and spend the afternoon at the Science Museum instead, also free, also in South Kensington, where the top-floor flight gallery is oddly moving. For a last dinner, the Harwood Arms in Fulham is a Michelin-starred pub whose venison scotch egg starter tends to convert people who assume pub food means soggy chips. Book a day ahead.

Get an Oyster card or tap contactless at any Tube station — the daily cap sits around £8 for zones 1 and 2, which covers everything in this itinerary. Walking days run about 7 to 8 kilometres each, mostly flat apart from Tube station stairs. London in late May and June currently hovers around 17°C with drizzle that tends to clear within the hour, so a packable rain jacket earns its luggage space more than an umbrella. One thing first-timers consistently get wrong: they pack Day 1 too tight and hit a wall by 3pm. The Westminster-to-South-Bank route above is deliberately lighter than Days 2 and 3, so you can call it early at 4pm without missing the best parts of the day.