That’s Tue’s kid? He’s like really good on a tiny 20" wheel, and pretty fast too.
In Cumbria, I think there’s only one place with any public/legal ‘North Shore’ type obstacles, which is Grizedale North Face Trail. It’s very very tame though, just wide wooden bridges.
There’s some scary looking north shore at Mabie, which is just over the border in Scotland. From what I’ve seen though, there are only a few riders who’d be able to ride it on a uni, and I dunno any who are under 12.