Rainy-Day London for Families
Building a single fixed family itinerary in London ignores the one variable you can’t control: the weather. Split your plan by indoor and outdoor instead.
For a wet day, the Science Museum’s Wonderlab is the strongest pick, though it’s worth knowing this is a separately ticketed hands-on gallery sitting inside the museum’s own free, mandatory-timed-ticket general admission, a two-ticket structure that catches families off guard if they only book the free entry. The Natural History Museum next door needs no separate ticket for its own kid-magnet draws, the blue whale skeleton “Hope” in the Hintze Hall and the Dinosaurs gallery both included in free general admission. For a bigger indoor block, the Madame Tussauds, SEA LIFE London Aquarium and London Dungeon combo runs £59 off-peak to £69 peak across a 90-day window; check current combo pricing on Viator before buying.
Two attractions that used to fill this exact rainy-day slot no longer exist: KidZania London closed permanently in January 2024, and The London Bridge Experience closed in autumn 2025, with the site now trading under a different name and concept entirely. Cross both off any older list still recommending them, since neither one is bookable in 2026 regardless of what an outdated search result might suggest.
Once the sky clears, four free outdoor options do more for a family afternoon than most paid ones. The Diana, Princess of Wales Memorial Playground in Kensington Gardens, a Peter Pan-themed enclosed space with a giant wooden pirate ship, is free and fully accessible, paired easily with the free Diana Memorial Fountain splash feature in Hyde Park. Greenwich Park adds a free deer park and a climb to the Royal Observatory. And the Regent’s Canal Waterbus between Little Venice and Camden Lock, a roughly 45-minute narrowboat ride through the Maida Hill tunnel past Regent’s Park, works as transport and entertainment at once.
ZSL London Zoo bridges both categories, largely outdoors but with covered sections, adult tickets from £31.80 online. GetYourGuide sells current ZSL Zoo tickets if you’d rather lock in a date before checking the forecast.
Verdict: keep the Wonderlab and the combo ticket as your standing wet-weather backup plan, and treat the free outdoor list as the one you actually build the whole trip around whenever the forecast finally cooperates for more than an hour or two. For the free national museums that also work equally well on any weather day, rain or shine, see the sightseeing guide .