Check in if available or drop luggage at London Marriott County Hall (your base) so you can start exploring immediately; the hotel is right on the South Bank by Westminster Bridge, ideal for families.
Have a family-friendly buffet breakfast at the hotel or the nearby South Bank cafés — convenient and quick for your first morning in London (hotel breakfast typically 7:00–10:30am).
Stroll through St James's Park to Buckingham Palace to secure a good viewing spot for the Changing of the Guard; the walk is scenic and stroller-friendly.
Watch the iconic Changing of the Guard ceremony outside Buckingham Palace — a free, colourful ceremony great for kids; it's typically scheduled for around 11:00am on Sundays (check the official schedule before you go).
Visit the Minecraft experience/exhibition (ticketed interactive exhibit aimed at kids) — a hands-on, playful stop that kids will enjoy; opening times vary so book in advance and confirm the slot (typical hours: 10:00–18:00).
Explore SEA LIFE London, right on the South Bank at County Hall — a compact, family-focused aquarium with sharks, rays and interactive tanks (typical opening 10:00–18:00; check last entry time before booking).
Enjoy a family-friendly afternoon tea close to your hotel — book a slightly earlier tea slot (around 4:30–6:00pm or an early 6:00pm) if you prefer to combine with aquarium and exhibits; many hotels/restaurants run tea services, check exact start times when booking.
Dinner with views of the Thames and Houses of Parliament at Gillray's Steakhouse & Bar (family-friendly menu and easy walk back to the hotel afterward).
Early hotel breakfast to fuel a full day — aim to be on the move by 8:15–8:30am for the Warner Bros transfer (hotel breakfasts usually from 7:00–10:30am).
Catch the train from London Euston to Watford Junction and the official shuttle to the studios; tours are timed-entry, so allow transit time and arrive for your booked start (studio opening times vary by tour slot, commonly from 9:30am onward).
Full immersive Harry Potter studio experience — sets, props, green-screen activities and the Hogwarts Great Hall; this is a full-day highlight for families and requires prebooked tickets and a set time slot (plan 3.5–5 hours on-site).
Take the shuttle back to Watford Junction and the train into London; you'll likely be back at your County Hall base in the late afternoon/early evening depending on your tour slot.
Relaxed family dinner — consider Covent Garden spots (many kid-friendly options) if you want to combine with an evening stroll or West End window-shopping. Restaurants typically open through dinner hours 5:00–9:30pm+.
Early breakfast at hotel or grab a packed breakfast for the coach/train; many Stonehenge tours depart early (typically 7:30–9:00am) to make the most of the day.
Either join a guided coach day-trip (most depart central London early) or take train to Salisbury and shuttle/bus to Stonehenge; coach tours are door-to-door and family-friendly, taking ~2 hours each way from London depending on traffic.
Explore the UNESCO World Heritage prehistoric monument with an audio guide or a guided tour — Stonehenge visitor centre usually open 9:30–17:00 (times vary by season), with scheduled arrival slots, so prebook tickets.
Head to nearby Salisbury town centre for a relaxed lunch and chance for kids to stretch their legs; cafés and family pubs in the city centre are open through lunch hours (11:30–15:00).
If time and energy allow, see Salisbury Cathedral (famous Magna Carta display) or return to London by train/coach — most day trips return in late afternoon/early evening.
Have dinner near your hotel to relax after a travel-filled day — simple family options on the South Bank or inside the hotel make for an easy end to the day.
Visit the Tower of London (open from 9:00am most days) to see the Crown Jewels, Yeoman Warders and historic towers — it's engaging for older kids and offers guided Beefeater talks (prebook tickets to skip queues).
Head to Borough Market for an informal, kid-friendly lunch with lots of options; market stalls are typically open 10:00–5:00 depending on the day and provide flexible choices for picky eaters.
Take a scenic City Cruises or similar boat from Tower Pier to Westminster — about 40–50 minutes with great views of Tower Bridge, the Globe, the London Eye and Houses of Parliament (services typically run 10:00–18:00; check sailings).
Disembark at Westminster and take photos of Big Ben, Westminster Abbey and the Houses of Parliament; this area is an easy riverside walk from your hotel if you want to revisit sights in daylight.
Early dinner in Covent Garden or a gastropub in Soho before your West End show — choose a family-friendly place with quick service so you arrive at the theatre relaxed (many restaurants accept reservations; typical dinner hours 5:00–9:30pm).
See a family-friendly West End performance (examples: The Lion King, Matilda, Frozen depending on availability) — most shows start at 7:30pm and run 2–2.5 hours with an interval; book seats in advance for the best family locations.
Head to South Kensington to visit the Natural History Museum — free entry, interactive exhibits and a dinosaur gallery are perfect for kids (open 10:00–18:00 typically; arrive early to avoid queues).
Take the tube to Regent Street and visit Hamleys — a multi-floor toy emporium that kids love — then enjoy some souvenir shopping along Regent and Oxford Streets (Hamleys typically open 10:00–20:00).
If you have spare time before departure, return to the South Bank for a last riverside walk, Jubilee Gardens play area or a ride on the London Eye (if not done yet; Eye open times vary seasonally).
Return to your hotel, collect luggage, and make your way to Heathrow/Gatwick/St Pancras/Euston as needed; allow generous travel time depending on your mode of departure.