Aquariums in Greater London

Only two of these seven are aquariums in the walk-through-tunnel sense, so it helps to sort them first. SEA LIFE London Aquarium, on the ground floor of County Hall on the South Bank, is the big one: one guide calls it the largest aquarium in London, with 14 zones including Shark Walk, Ray Lagoon and Penguin Point. Reviewers praise exhibits pitched at child height and the tunnel, and repeatedly flag expensive food and photo packages. One review site notes there is no cafe inside, just vending machines and snack points, and warns it is packed on rainy days and in school holidays. A Tripadvisor listing rates it lower than Google does, and one reviewer there criticised the penguin enclosure for lacking natural light.

Sea Life Chessington World of Adventures Resort offers a similar Ocean Tunnel experience aimed at 3 to 9 year olds, with supervised touch pool sessions, though reviewers describe congested spaces and consistently dark lighting. At the other end of the scale, Horniman Aquarium in Forest Hill is four rooms and 10 to 30 minutes, which suits toddlers and bores older children. It sits inside Horniman Museum and Gardens, where the galleries are free and the aquarium and butterfly house are paid extras worth pre-booking at half term.

The rest is water without fish tanks. National Maritime Museum in Greenwich is free, and its AHOY! gallery for under-7s needs free weekend tickets booked ahead. Victoria Park Boat Hire has stable pedal boats on a shallow lake with life jackets for children 10 and under. Valentines Park Boating Lake in Ilford is rowing boats, cash only, with staff supplying duck food and child-sized oars, plus a large playground on site.