Aerial footage of many British landscapes shows that rock type has a crucial influence. We focus on limestone and slate.

01.45 — 03.25

Carboniferous limestone scenery above ground around Malham is explored.

03.25 — 06.42

How subsurface features develop.

06.42 — 08.47

The effect of limestone on vegetation, field boundaries, homes and industry in north Yorkshire.

08.47 — 10.48

The variety of limestone in the British Isles — in particular, Portland stone and its prominent use in public buildings.

10.48 — 12.08

The mountainous landscape of slate in north Wales. The useful qualities of slate as a roofing material are demonstrated.

12.08 — 13.46

We look inside one of only two remaining factories processing slate for roofs.

13.46 — 17.40

Roofing slate has been sold all around the world. We look at the decline of the industry in the twentieth century, with its legacy of tips and abandoned buildings.

17.40 — 18.27

For prestigious new buildings, such as the new British Library, slate is still the best choice for roofing, especially in polluted cities.

18.27 — 18.51

In contrast, limestone buildings in the capital, such as the Houses of Parliament, must constantly fight the problems of chemical weathering to which the rock is prone.