But what I didn't know back then is that there's a festival especially for the under 10s. Lollibop. Bookmark it, it's really rather good.
For our two 4 year olds it was everything a festival should be. There was a host of CBeebies characters on the two main stages - Hook and Line from Swashbuckles, Mister Maker, Mr Bloom with his veggies.
Straight after the pirate act we headed for the Science Museum tent where we completed three science-y tasks and earnt a sticker. It was a real bonus that venues like the Science Museum and Southbank Centre were there - adding some 'educational' aspect to sugar-y sweetness of the free Haribos being thrown into the crowd.
My two were face painted to become a glittery flower and a glittery spider man (free in the press bit, lucky us) where we could have met Alex Winters - the Welsh one on Cbeebies and presenting on the main stage - if only I'd been a bit more clued up.
As well as the main acts there was plenty more to do and see at the Duplo tent, the Ladybird books at the Lollibooks Arena which was right next to The Roald Dahl Museum and Story Centre bit where two performers did a brilliant rendition of The Three Pigs to a small but attentive audience.
We got festival-ised in the Southbank Centre's Charity DJ tent where Oscar made a crown out of gold card and Pritt Stick and took part in the hat parade. We saw Natalie Cassady having a hug with Postman Pat. And Caitlin bashed on an old car wheel with a stick as part of the Junk Orchestra - another sound Southbank initiative.
As I was trying to leave we got distracted by some colouring in tables by a yoghurt stand, and then the pair of them saw the Skylanders castle and ran off to have a go at that.
Such a great day out and, dare I say it, better than Glastonbury - if you've got under 10s.