- Denmark's Rabjerg Mile is the largest migratory dune in northern Europe
- Giant dune has swallowed up buildings including a medieval church and lighthouse accommodation
- The area doubled as a desert in 1915 silent film "The Secret of the Sphinx"
(CNN)On the whole, Denmark is pretty deserving of its reputation as a neat, orderly place.
So it's a surprise to discover a sand dune the size of a small desert roaming around the countryside unchecked, destroying farmhouses, churches, roads and anything else that gets in its way.
While Legoland's miniaturized landmarks may be more famous, Northern Jutland's claim to be home to "Denmark's equivalent of the Sahara" doesn't look quite as ridiculous as that sounds when you're actually standing amid the windswept white sands of Rabjerg Mile.
Certainly a budget Nordic remake of "Lawrence of Arabia" wouldn't be out of the question.
Covering an area of 1.5 square kilometers and containing 3.5 million cubic meters of sand, Rabjerg Mile is the largest migratory dune in northern Europe.
In fact, the dune played a starring role in the desert epic of its day.
In 1915, Danish filmmakers erected a sphinx and a pyramid as the backdrop for "The Secret of the Sphinx," one of the more ambitious productions of the Scandinavian country's so-called "golden age" of silent cinema.
At the time it was the largest and most expensive film set ever built.
Sepia-toned photos of actors in flowing robes suggest a reasonable approximation of the wonders of ancient Egypt was achieved.
These days, it's the undisturbed natural beauty of the dune and the thriving ecosystem of the wetlands left in its wake that are the star attractions for visitors that come to hike its slopes each year.
"Listen to the quietness," says Villy Hansen, our group's guide for the day and a dune ranger for 15 years. "It's very special. There are not many places where you can hear nothing. And look at the endless horizon."
Only the croaking of a few frisky natterjack toads disturbs the peace as we sit atop the highest point, 40 meters above solid ground, enjoying a view that stretches from the waters of the Skagerrak, a straight off Denmark's western coast, to the Kattegat Channel leading to the Baltic in the east.
Understanding how so much sand ended up in one place requires a Dummies' Guide to millions of years of geological history, which Hansen illustrates by scratching out lines and arrows with a stick and shaping ridges with his hands.
"This sand was cliffs and mountains in the period when the tectonic plates were taking land from each other," he explains.
More sand was added to the mix during the ice ages, as the landscape was crushed and re-sculpted by glaciers.
Rabjerg Mile's documented history begins in the 1700s.
By then Denmark had been plagued for centuries by sand drifts that destroyed farmlands, buried buildings and forced villages to be abandoned.
"It is to be feared that the whole of North Jutland will be covered with sand and virtually laid waste," a city official in Aalborg wrote in 1726.
In the 19th century, the government finally took steps to tame the dunes, planting millions of trees and shrubs to check their movement.
But Rabjerg Mile was left to roam as an active reminder of how the landscape had been.
Since then it has continued to move northeastward at an average rate of about 15 meters a year, covering nearly five kilometers since measurements of its movement began.
Hansen says the dune appears to be turning left and speeding up because of variations in wind direction he believes are a consequence of climate change.
"We don't get so much wind from the west anymore. It had been moving from Skagerrak to Kattegat but now it looks like it will go back to Skagerrak.
"Maybe it will change for three years or a hundred years, who knows? Nothing is certain nowadays."
Giant sand castle
More worrying for Hansen is the threat posed by rising sea levels to an area that is effectively a giant sand castle.
"If the sea rises one meter then I won't be living here anymore," says Hansen. "You could go out toward Norway where the sea is 800 meters deep, take all the sand that has built up here over 9,000 years and count to three and there would be nothing left.
"The land here is dynamic, being built up and torn down, and this place is a monument to all of that."
A few kilometers south stands another monument to the natural forces at work on this coastline.
When the lighthouse at Rubjerg Knude was built at the end of the 19th century, it stood amid green fields on cliffs 60 meters high and set back 200 meters from the sea.
Now, only the tower is visible, the two-story building beneath it swallowed up by sand and the steep drop to the beach just a few footsteps away.
The lighthouse was switched off in 1968 and converted into a museum.
That had to be abandoned in 2002, by which time staff were serving ice cream to visitors out of a first floor window.
"Every time I come up here it is different. It is a fascinating landscape," says local guide Jakob Nielsen, pointing at the streaks of sand and clay in the cliff face.
Most of the erosion is caused by winter storms, which wash away the clay and loosen the sand, uncovering an archaeological cross-section of human history.
"You see the dark layers? Those were Viking fields. And those layers higher up were wheat fields 500 years ago," says local artist John Kristensen, who has been painting Rubjerg Knude lighthouse every year for almost 40 years.
"If we go down to the beach it's possible we'll find something from the Stone Age."
When Kristensen began painting he had no idea he was charting the lighthouse's demise.
When he realized it, he set about trying to buy back his earliest paintings to complete the series, though so far without success.
"The lighthouse is a reference point, but the most fascinating things are the landscape and the light. They are constantly changing," he says.
Kristensen may not have to drag his easel to the top of the dunes many times more.
The lighthouse is expected to crash into the sea by 2020 if the cliff continues to retreat at its current rate, though bad weather over the next few winters could accelerate its demise.
"Maybe it will be a reef down there," he says, pointing a paintbrush toward the beach below.
"Perhaps I'll sit on it and try fishing instead."