The Jizera dark sky area covers an area of almost 75 square kilometres. This darkness reserve is located in an almost uninhabited part of the Jizerské Hory mountains, far enough away from big cities. It stretches along the upper reaches of the Jizera River in the territory of Bohemia and Poland. It is the area of the densest darkness in the country.

Thanks to artificial light, cities have become islands of light that can easily be seen from orbit in the night-time hemisphere of the Earth. However, the indiscriminate use of artificial light has led to a phenomenon called light pollution. The extent of this phenomenon is so great that it must be placed alongside such problems as chemical pollution of the atmosphere, water, and soil. However, the Jizerské Hory mountains will remain dark – the Jizera Dark Sky Area was created as part of the International Year of Astronomy in 2009 and protects the dark skies on both the Czech and Polish sides of the mountains. Unlike cities, where only about 50 stars are normally visible, you can see up to 2,000 stars from Jizerka in good visibility.

On the Czech side, the dark sky area extends from the Martinské Údolí valley, Václavík’s well through the settlement of Jizerka to the Smrk mountain, in Poland it continues along the High Jizera Ridge, encircling the Great Jizera Meadow and the settlement of Orle. This is the first international area of this type in the world, but in several countries of the world there are already darkness reserves.

The area is established to inform the general and professional public on the local preserved night environment, to educate on this issue, to promote the protection of the night environment with an emphasis on dark skies and is the basis for the protection of the natural environment in the area from light pollution. In Jizerka, under the dark skies of the Jizerské Hory mountains, there are regular astronomical observations with telescopes for the public. There are also information panels on the protection of the night sky and the night environment.