Around 150,000 years ago, during the Saalian glaciation, the ice sheets that covered northern Europe pushed south as far as the central Netherlands - and then stopped. They stopped right here. As they ground forward they bulldozed enormous quantities of sand and gravel into ridges along their southern edge. Then the climate warmed and the ice melted away, leaving the ridges behind. These ridges are what you walk on at Veluwezoom. They are technically called push moraines, and the slow-water streams that ran off the melting ice carved valleys between them. Many of those valleys still exist - dry now, but unmistakably stream-shaped. During the more recent Weichselian glaciation the ice did not quite reach the Netherlands, but its winds blew dust and sand that gathered in the valleys, eventually forming the fertile loess soils of the southern Veluwe.

Around 1900, as Dutch cities grew rich and crowded, the urban upper class developed a sudden hunger for woodland holidays. Inns sprang up across the Veluwe. The wealthy built country estates among the hills. By 1930 the importance of protecting these landscapes had become obvious enough that Veluwezoom was declared a national park - the first in the Netherlands. The wider Veluwe region now totals about 1,100 square kilometres of forest, heath, and drift sand; Veluwezoom itself covers 50 square kilometres of that. The neighbouring Hoge Veluwe is more famous internationally because of its Van Gogh museum. Veluwezoom is wilder.

The defining colour of Veluwezoom changes by month. In late summer the heathlands turn purple - common heather, cross-leaved heath, gorse, broom - and the Posbank ridge in particular becomes one of the most photographed landscapes in the country. Underfoot in spring you find blueberries and lingonberries on the sandy patches. In the old forests of 't Asselt and the Onzalige Bossen, bracken grows under oak and birch. Underneath the planted pines on the Eerbeeksche Veld, wavy hair-grass forms entire silver-green meadows. The wildlife is correspondingly varied: red deer, fallow deer, roe deer, and wild boar roam freely. Foxes, badgers, stoats, and pine martens hunt them in turn. Of the seven reptile species native to the Netherlands, six live in this single park - including the European adder, the country's only venomous snake. Boar with piglets are the practical hazard. The advice is simple: do not approach them.

If you only have a half-day at Veluwezoom, you go to the Posbank. This is the long heath-and-fern slope on the park's southern edge, rising gradually from the village of Rheden up to a viewpoint that has become almost a national pilgrimage site for people who want to remember that the Netherlands has elevation. The visitor centre at Heuvenseweg 5a in Rheden rents bikes. The cycle paths through the park are good. Cars are restricted to a few marked roads and would not get you far anyway. The honest way to see Veluwezoom is on a bicycle or on foot, climbing slowly through the trees onto the open heath where, on still days, you can hear nothing but skylarks and the occasional black woodpecker drilling into deadwood.

There is something quietly radical about Veluwezoom existing at all. The Netherlands is one of the most densely populated, most thoroughly cultivated countries on the planet. Almost every square metre of it has been engineered: drained, dyked, planted, navigated. To set aside fifty square kilometres of glacial moraine and let it run mostly wild - with deer and boar and adders - was a deliberate cultural decision made in 1930 by a generation that suspected the country might one day need its wild places back. Ninety-six years later, with bicycle paths threading through heather that bees still find, the decision looks better than most. Camping is not allowed inside the park. You are expected to come, walk, look, and go back to your hotel in the next village. The park belongs to itself.