Krkonoše as a biogeographical crossroads

The extraordinary value of the mountains in terms of natural history is associated with its special positioning amidst Europe. The range is the highest of the Hercynian mountains and stretches just above the 50th parallel north, its ridges rising significantly above the alpine tree line. Therefore, it presents an isolated mountainous patch in the middle of the vast plains and hills of Central Europe. Any similar mountains in Scandinavia, the British Isles or south-west Europe are hundreds of kilometres away. This makes the mountains a natural barrier, inhibiting cold and wet winds blowing in from the west and the Atlantic Ocean. In the past, important events occurred here that have influenced the development of Central Europe's landscapes and natural systems.

In the period of recurrent Quaternary glaciations, a mighty Scandinavian glacier moved from north to south, meaning northern tundra penetrated Central Europe along its southern boundary. The ice mass then stopped near the northern foot of the Krkonoše Mountains. Alpine glaciers were bigger too, extending closer to the Czech Basin. Non-iced ridges of Krkonoše became, at that time, a natural crossroads at which the northern and alpine natural world met. This significantly influenced the richness of species and diversity of these small European mid-mountains.

When it became distinctively warmer, approximately 20 thousand years ago, the glaciers retreated to the north or into the high elevation of the Alps. The peak ridges of Krkonoše then became an isolated place, divided by vast Central European woodlands from other mountain ranges. The same became a reality for many examples of plant and animal life from the ancient ice ages, the glacial relicts. Furthermore, some species of plants (and a few animals) evolved here that cannot be found elsewhere in the world. Called endemic species, they have made the mountains famous due to their high numbers.