Oblík NNR covers the dominant peak (509 m) of the Chožovské středohoří geomorphological district. The NNR was declared on a territory of 20.50 ha in 1967 and lies to the north of the town of Louny in the west of the Ústecký kraj – Ústí nad Labem Region. The subjects of the protection are the valuable thermophilous communities on the alkaline geological basement which holds and radiates heat in the driest part of the Czech Republic. The species composition is closely bound to the exposition and morphology of the slopes, the elevation above sea level and the differing pedogenetic processes.
Oblík is a distinctive neck in the form of a truncated cone, with an elliptic shape stretched to the SW and NE, and built of nepheline basanite. The neighbouring peaks of Srdov and Brník are built of olivine nephelinite. All three peaks underwent a similar geological development as they were formed in the same period and along the same tectonic line. These peaks are among the most typical representatives of the so-called “linear eruptions” in České středohoří PLA. Levelled surfaces on the Cretaceous rocks (sediments of the Březno, Teplice and Jizera formations) are found between the necks. Landslides are a characteristic feature as the accumulations of neovolcanic rocks exert additional load on plastic marlstones on the rugged slopes. These landslides take place during wet weather periods.
Oblík is a model territory for the study of steppe vegetation as the vegetation units which are found here differ in their average species diversity. It is debatable whether the slope steppe vegetation communities on Oblík correspond to the zonal classification of steppe growths. Various steppe types have been identified and named here including feather-grass meadow steppe, herb-rich feathergrass steppe and varied meadow steppe. The range of the Erysimo crepidifolii-Festucetum valesiacae and Carici humilis-Festucetum sulcatae associations have been mapped here and also their connections to the expanding shrub communities (compact growths in several places at the foot of the slopes and in gulleys with higher soil moisture content higher up the slopes). The following specially protected species grow abundantly on Oblík: yellow pheasant’s eye (Adonis vernalis), purple mullein (Verbascum phoeniceum), St. Bernard’s lily (Anthericum liliago), the milkvetches Astragalus excapus and Astragalus austriacus, purple milkvetch (Astragalus danicus), the hyacinth Muscari tenuiflorum, the oat-grass Helictotrichon desertorum and the feather-grasses Stipa joannis, Stipa pulcherrima, Stipa dasyphylla and Stipa tirsa.
Research has proven the occurrence of 81 vertebrate species of which 66 are bird species. Protected vertebrate species found here include the smooth snake (Coronella austriaca), wheatear (Oenanthe oenanthe) and the hoopoe (Upupa epops). The invertebrate fauna on Oblík is unique and unusually rich with many protected and very rare thermophilous and xerophilous species such as the purse-web spider Atypus muralis, Nickerl’s fritillary butterfly (Melitaea aurelia), the tiger moth Watsonarctia casta, the dor beetle Sisyphus schaefferi and the endemic ground beetle Parazuphium chevrolatii rebli.
The northern slope of Oblík is forested but almost all of the woody plants are bush-sized growths and only a few limes, maples and ashes are taller than 5 metres. Predominant species in the shrub layer are hazel, hawthorn, rowan, guelder rose, cotoneaster, Cornelian cherry, dogwood and wild rose. Species represented in the herb layer are dog’s mercury (Mercurialis perennis), asarabacca (Asarum europaeum), hepatica (Hepatica nobilis), the bulbous fumitory (Corydalis cava), hairy violet (Viola hirta), baneberry (Actaea spicata) and cowslip (Primula veris).
The grassland growths on Oblík were formerly grazed by cattle and especially sheep. A return to grazing would be beneficial as it would help to restrict the advance of tall-herb and shrub communities. The summit of Oblík is a popular destination for hikers with views over the surroundings. Oblík, together with the neighbouring peaks of Srdov and Brník are included in the Natura 2000 network as a proposed Site of Community Importance to protect the steppe communities and the grasshopper Stenobothrus eurasius.