From the natural geometry of the Giant''s Causeway to the sarsen slabs used to build Stonehenge, we are surrounded by evidence for the extraordinary geological forces that shaped the British Isles. Running coast to coast through Devon is ''Sticklepath'', Britain''s ''San Andreas'', a geological fault with the two sides displaced horizontally by several kilometres, all within the recent geological past. The Sticklepath Fault is just one manifestation of the rich tectonic history of the British region since the asteroid collision that ended the reign of the dinosaurs, 66 million years ago. Raised out of the Chalk Sea, the original Albion was a thickly forested island a thousand kilometres long,surrounded by chalk cliffs, punctuated with great volcanoes, and the site of two trial ''spreading ridge'' plate-boundaries. As the volcanoes shifted west, and Greenland separated from Europe, the wind-blown volcanic ash laid the strata on which London was founded. The vertical Needles, kno
