Råbjerg Mile is a migrating coastal dune between Skagen and Frederikshavn, Denmark. It is the largest moving dune in Northern Europe with an area of around 1 km² (0.4 mi²) and a height of 40 m (130 ft). The dune contains a total of 4 million m³ of sand. The wind moves it in a north-easterly direction up to 18 m a year. The dune leaves a low, moist layer of sand behind it, trailing back westwards towards Skagerrak, where the Mile originally formed more than 300 years ago. Over 250,000 people visit the dune every year.