If your children are fans of Barnacles, Kwazii and the rest of the Octonauts crew, the Horniman Museum in Forest Hill has an exhibition that will have them absolutely buzzing.
Voyage to the Deep runs until 1 November 2026 and the whole thing is built around a submarine. You step inside the legendary Nautilus and from that moment, children are completely transported. It is genuinely immersive in a way that a lot of children’s exhibitions promise but don’t quite deliver. The space itself does the heavy lifting before you’ve even read a single fact.
And there are plenty of facts to read. Octonauts creature reports are dotted throughout, which works brilliantly for young children who already know the format from the TV show. It turns learning about ocean life into something familiar and engaging rather than a passive read-the-board experience. Children were actually stopping to take things in, which is not always a given with this age group.
The play elements are well considered. There are little beds to clamber into, a small kitchen area to explore, and a slide, which provides all the encouragement some children need to stay engaged for another twenty minutes. It strikes a good balance between active play and discovery, so visits have a sense of purpose beyond simply keeping moving.
The free Octonauts trail is a worthwhile addition. You pick it up at the ticket desk or inside the exhibition itself, and it takes children on mini-missions around the wider museum and gardens. It extends the visit considerably and gives a real sense of exploring the whole site rather than heading straight back to the entrance.
That wider site is genuinely worth your time. The Horniman sits within 16 acres of beautifully kept gardens with sweeping views across London, and the free Animal Walk is a particular highlight for younger visitors. Home to alpacas, pygmy goats, sheep, rabbits, guinea pigs and chickens, it is a walk-through enclosure that children find completely captivating. Factor in the bandstand, the sound garden with its giant playable instruments, and space to sit and eat a packed lunch, and you have a full day without much effort.
If you live nearby, it is worth looking at annual membership. Starting from £42, it covers free entry to the Aquarium, Butterfly House and ticketed exhibitions like Voyage to the Deep. For a family making two or three visits a year, it pays for itself quickly, and it takes the pressure off the day entirely knowing you can leave and come back without paying again.
Booking in advance is recommended for the exhibition, and arriving early makes a difference. By mid-morning on a weekend it fills up quickly, and while there is no timed entry limit once you are inside, it can feel crowded as the day builds.
For what you get, the price feels reasonable. It is the kind of day out children are still talking about on the drive home.
Voyage to the Deep, Horniman Museum and Gardens, Forest Hill, SE23 3PQ. Open until 1 November 2026. Book at horniman.ac.uk.