London Aquarium

You're looking at one of London's biggest draws for anyone with kids in tow - the Sea Life London Aquarium, right on the South Bank between Westminster Bridge and County Hall. It's a proper underground setup, which means you descend into a darkened tunnel of tanks where sharks glide past, jellyfish drift about like living lava lamps, and the occasional ray glides through with unsettling grace. The highlight is definitely the walk-through tunnel where the water curves above your head and you're surrounded on three sides. Kids absolutely lose their minds over it.

The place spans multiple floors of aquarium space - everything from seahorses to stingrays to those terrifying anglerfish that lurk in the deep. Most visitors spend between two and three hours here, which is about right before everyone gets tired of reading the information boards. It's indoor and climate-controlled, which makes it brilliant on a rainy London day.

You'll want to check the website for current entry fees and opening hours before you go - these can shift seasonally. It's not cheap, but if your family are marine life enthusiasts, it delivers. Lovat Parks sits just 1.4 miles away, making it a sensible base if you're planning a longer South Bank adventure combining the aquarium with the London Eye or museums nearby. Book online in advance if you can - it usually saves money and cuts queue time considerably.