Tony Robinson: Coast to Coast (C5, 8pm)

THE presenter visits Eden Valley, Cumbria, where he makes a dramatic ascent to the limestone-paved Great Asby Scar, the last evidence of a 300 million-year-old tropical sea.

Smardale Gill viaduct has Tony marvelling at its engineering genius, before he investigates the 21st-century technology driving a traditional dairy.

The actor and history buff gets a masterclass working with border collie sheepdogs before heading to Nine Standards Rigg, a summit high on the backbone of Britain, where he contemplates the origins of the huge drystone cairns that dominate the skyline.