Soundpit, Royal Festival Hall, review ★★★★★

No parent likes it when their kid goes in the sandpit: it's dirty, it's messy, it typically involves standing outside in the wet, cold weather and it often ends in tears (sand in the eyes or similar).

The Southbank's Soundpit, however? It's the stuff kids' activity dreams are made of: we attended with four children, ranging in age from 17 months to 8 1/2, and they all found something to delight them about the experience. No one cried, and better yet – emerging after the session as a grownup, we felt relaxed. Not an easy feat at half term (or with four kids, ever).

The premise? Soundpit, a sensory experience in the Royal Festival Hall, explores what sound might feel like, what music might look like: is it undulating jellyfish and colourful underwater life? Is it the infinity symbol, replicated infinitely? Is it a diamond ring you dig and dig and dig for? Created by artist Di Mainstone, Soundpit is a feast for the senses with music, flickering lights and amazing reflections and shapes cast into the sandpits, which you can manipulate and design to your imaginative delight.

Photo: Pete Woodhead

The kids were loving it: there were sandpits you could put your feet into (or whole body, as most of the kids were doing – one of my co-reviewers was making sand angels, diving into the sand and repeatedly demanding to be half-buried, mermaid-style). There were pits to stand next to and play with using your hands. Since the images constantly changed – and then changed again, depending on what the children were doing with the sand – there was no end to the entertainment as new shapes, colours and patterns continued to emerge and kids got deeper into their fantasy role play.

'I felt really happy and calm, digging with my hands, expressing my feelings, figuring out different shapes and fishy patterns and listening to the music,' our 8-year-old co-reviewer said, while the 3-year-old declared: 'I liked all the places where you could put your feet and all of the shapes like triangles, squares and circles.'

For us, the best part was how it managed to entertain a toddler going for the baby sensory experience as well as the over-10s. As any parent will tell you, that's near impossible to achieve. Also, the sand didn't feel wet, dirty or unpleasant. It felt like a magic ingredient you wanted to keep moulding and sifting. And when sand did drop on the floor, no one batted an eyelid – messy play at its best occurs when exhausted parents aren't the ones who have to clean it up.