Tranum Klitplantage was founded in 1918 to combat sand drift, replacing farms and marshes. The state bought the area, but many old houses have now been demolished, although traces of the old building and garden plots are still evident.

Establishing Tranum Klitplantage required considerable labor for sand reduction, ditch digging and forest roads. Now the plantation extends over 3910 ha, with forest areas mainly consisting of sitka spruce on low-lying areas and Scots pine on higher, dry areas, as well as large dune and marsh areas.

Tranum Klitplantage's characteristic pine forests are open to light, and the older they get, the greater the biodiversity. Under the pines, heather, cross-leaved heather and herbs such as tormentil and catsear. The forest houses habitats for fungi, lichens, mosses, insects, butterflies and birds such as woodlarks and nightjar.

Numerous species in Tranum Klitplantage thrive in the clearings and along the roadsides. When the light reaches the ground, various herbs thrive and a wealth of flowers appear, to the delight of insects and butterflies.

4-5000 years ago, when land uplift began to take hold, after the Stone Age and Litorina seas had flooded large parts of Vendsyssel, the old seabed was gradually exposed to drying. It is on this Stone Age surface that the marshes now exist.

Today, the marshs form a fascinating natural area with a diversity of animal and plant life. In the past, the marshs were characterized by significant sand drift, while at the same time they functioned as areas where people collected fuel in the form of peat.

There are marked paths leading through the marshs and they are carefully tended to prevent overgrowth. If you move quietly through the area, you can experience the rich flora and fauna, including impressive birds of prey such as Eurasian goshawk, both the short- and the long-eared owl, marsh harriers and hen harrier.

The marshs house a diversity of plant species that thrive in the acidic and wet growing conditions. Devil's bit, a distinctive plant, is the host plant for the endangered marsh fritillary butterfly, which can be observed in the month of June.

Each year, regional plays are organized in Sandmosen and Koldmosen, where historical plays tell about the life and work of the peat diggers in the bogs, the peat diggers and their life in the bog.