Thy National Park (Danish: Nationalpark Thy) is a protected area in Thy, Denmark. It opened to the public on August 22, 2008. The park is located in Northwest Jutland, along the coastline between Hanstholm and Agger Tange. It stretches 55 kilometers (34 miles) from north to south and 5 to 12 kilometers (3.1 to 7.5 miles) from east to west. The total area of the park covers 244 square kilometers (94 square miles).

The unique landscape of sand dunes and grassy heaths in Thy was officially chosen on June 29, 2007, to become the first national park in mainland Denmark. This followed the establishment of the Northeast Greenland National Park in 1974. Additional national parks were created later.

According to the Danish government's Forest and Nature Agency:
Thy National Park is not only a place for visitors to enjoy.

Nature

The landscape includes windy coasts and dune systems, which may be bare, covered by heaths, meadows, or plantations, and often have many conifer trees. Low-nutrient wet hollows, a type of bog, are also found, and small ponds and lakes are scattered across the area. Evidence from the Stone Age Littorina Sea can be seen here, such as limestone cliffs along the coast or inland.

Drifting sands in Thy have caused problems for people for many years, moving into their homes and land. Efforts to control the sand began around the year 1800, when grasses and trees were planted. Marram grass and conifers were used mainly, and the dune plantations today show the long effort to protect the land from nature’s power. These plantations helped stop the sand, provided jobs, and gave wood for fuel. They also allowed new animals, like red deer and roe deer, to live in the area.

Trees and grasses are not the only plants in the dunes. The sandy dune heaths in Thy National Park are a rare habitat in Europe and are protected by law. These heaths are important for the national park and require careful work to protect them from other plants. Grazing by large animals, removing trees, and controlled fires are used to help the heaths grow. The heath plants may seem simple, but they include many types, such as common heather, sand sedge, marram grass, black crowberry, bell heather, and lichens. The heaths attract many birds, including rare species like cranes and wood sandpipers, and support animals like the natterjack toad and insects. The wet hollows have different plants, such as bog bilberry, bayberry, marsh gentian, cranberry, and sundew.

In the northern part of the park is the Hanstholm Vildtreservat game preserve, started in the 1930s. It covers about 40 km² and has the largest connected sandy heath in Denmark. About 60–70% of the area is open to the public, except from April 1 to July 15, when birds are nesting. The preserve is home to many bird species, including the rare European golden plover, which only breeds in this area. Coastal dunes have rare plants like beach morning glory and scots loveage, found only here and possibly a few other spots. Some lakes and ponds in or near the preserve have rare plants, such as water lobelia, quillwort, chara, and slender naiad. Wolves were last seen in Denmark in 1813, but several sightings have been reported in Thy and the preserve since 2009. A dead wolf found in 2012 likely came from Germany.

Many plants in the park are edible or have edible fruits, like blackberries, cranberries, sea-buckthorns, and seakale found on beaches. Some plants, like scots loveage, are rare and protected. Parts of the park are protected as a bird area, Ramsar site, Natura 2000 area, and other conservation zones.

• The black-tailed godwit, a globally near-threatened bird, lives in Thy National Park.
• The Hercules ant (Camponotus herculeanus) is found in some plantations here and is rare or absent elsewhere in Denmark.
• Black crowberries are among the edible plants in the national park.
• Views of the dune heaths in Hanstholm game preserve are available.
• Slender water lobelia is an indicator of clean lakes and ponds in the park.
• The pillwort fern, a globally near-threatened plant, grows in Thy.

Cultural history

The cultural history in Thy National Park is as old as the land itself. At the end of the last Ice Age, the ice melted and receded. The land began to rise, and early Stone Age people settled there. Their activities are still visible in the landscape, such as dolmens, burial mounds, kitchen middens, and areas where flint tools were made.

As the land rose from the sea, human activity increased. Thy became an important place during the Bronze Age. Archaeological evidence, such as ancient settlements and many barrows, can still be seen, especially near Hanstholm. Over time, drifting sands and dunes covered some remains. However, the number of visible mounds shows how active the area was during this time.

Human activity continued into the Iron Age, Viking Age, and Middle Ages. Each period left its own marks in the park, often connected to the North Sea. At some point, the environment around Thy changed. For many years, the land was overused through too much grazing and cutting down trees. Eventually, drifting sands took over and shaped the area for centuries. Large efforts to stop the sand drifts began around the year 1800. It took more than 100 years to succeed.

In modern times, the most dramatic evidence of human activity is the German bunkers built during World War II. When Denmark was occupied, the German army built strong defenses in Thy and along the west coast. Thy was part of the Atlantic Wall, a defense system to control the North Sea, limit Allied forces, and protect against the British air force. Many concrete bunkers and fortifications remain today. Some are abandoned or ruined, while others are restored and used as museums. In the northern part of the park, the Hanstholm Fortress is a modern museum about World War II events. Five restored bunkers and batteries are located along the coastline in the national park.

• Dyrhøj: A Bronze Age burial mound in Thy National Park.
• Plantations helped stop the sand drifts, but it took more than 100 years.
• An old fisherman’s house in Agger.
• Some cannons at the Hanstholm Fortress, now a World War II museum.