Råbjerg Mile

The largest moving dune in Northern Europe, and the only significant stretch of migrating sand left in Denmark: two square kilometres, forty metres high, four million cubic metres of it, walking northeast at up to eighteen metres a year. It formed on the Skagerrak coast more than three hundred years ago and leaves a low damp trail of sand behind it as it goes. Shifting dunes were a genuine emergency in the sixteenth and seventeenth centuries, driving people inland, and by the 1950s planting had brought them under control everywhere else. The Mile was deliberately left alone.