The range stretches from the Lusatian Mountains in the northwest to the Krkonoše in the southeast. The Jizera Mountains comprise the sources of the Jizera river, as well as of the Kwisa and the Lusatian Neisse. The major part in the south is formed from granite, in the northern part from gneisses and mica schists, with some areas formed from basalt. The weather conditions are characterized by above-average annual precipitation. On 30 July 1897, the measuring station at Nová Louka recorded a daily precipitation amounting to 345.1 mm, still an unbroken European record.
The first settlements in the area date back to prehistory. Later on, Celts, German tribes resides in the valleys until they left in 5th century. Later came Lusatian Sorbs. In the 14th century, German-speaking colonists came and started clearing of the dense primeval forests. Permanent settlements were established. In the 16th century, several glass works were founded. Glassmaking had a profound effect on the ecosystem. The primeval forest was gradually replaced by fast-growing spruce monoculture. Other important industries included tin-mining, metallurgy and textile. The Tabulový kámen on the northern edge of the Smrk Mountain marked the border between the properties of the Counts of in Friedland, Bohemia, the von Gersdorff family from Meffersdorf, Upper Lusatia and the Counts of Schaffgotsch from Schreiberhau, Silesia. In the second half of the 20th century the character of the Jizera Mountains changed completely. The German population of the area was expelled in 1945 and replaced by Poles on the now Polish and Czechs on the Czechoslovakian side of the mountains. The ecosystem was badly hit by emissions, produced by lignite fired power stations located in the Zittau basin, part of Europe's ecological Black Triangle. Weakened spruce forest, less resistant against various types of parasites, were on the verge of extinction. The higher parts of the mountains, once densely wooded, became largely treeless, in part also because of excessive deforestation. New roads cut through the once-secluded landscape. The situation improved only after the fall of communism in 1989. Open-pitcoal mines in the former East Germany were closed, as well as several major power plants. Emission filters were installed at the immense Turów Power Station in Bogatynia on the Polish side of Lusatian Neisse. At the same time large-scale reforestation projects were started.
Large parts of the Jizera Mountains are under some form of protection. In the smaller Polish parts, the peat bogs in Jizera Valley are part of a relatively small nature protection of about 5 km²; Rezerwat Torfowiska Doliny Izery. In the Czech parts, Jizera Mountains Protected Landscape Area covers 368 km², or almost all of the Czech parts of the mountains. This landscape protection contains several reserves, including the Jizera Dark Sky Park, dedicated to star watching.
Literature
Weiss, Siegfried Moje Jizerky - Jizerské hory v proměnách času, Mein Isergebirge - Das Isergebirge im Wandel der Zeit, My Jizera Hills - The Jizera Mountains through a changing of time, Buk
Nevrlý, Miroslav Kniha o Jizerských horách, 3rd edition, Civitas
