Yorkshire looks different in the dark. Helen Mark looks up into the heavens and deep underground for a new understanding of England's biggest county.

Off-road cycling in the Dales becomes a lot more thrilling when you strike out into the dark and, armed with an infra-red nghtscope you realise just how busy the forests of the North York Moors National Park are after sunset.

Helen will also be discovering how the Brontë sisters filled the long nights in the Haworth Parsonage and mining precious Blue John in the caverns of the Peak District.

Producer: Alasdair Cross.