Anyone out winter walking in the Yorkshire dales will probably be familiar with the dramatic scenery of limestone pavements. Distinctive and beautiful, they can also be found elsewhere in Britain, as well as in mainland Europe and Canada – not to mention in Harry Potter and the Deathly Hallows, where Harry and Hermione set up camp in a rocky clifftop. Limestone pavements were formed more than 300 million years ago in the Dinantian period, when the ice sheets scraped away soil, leaving limestone rock exposed. Over time, rainfall wore away the rock into the uneven patterns that we see today.…