The nature reserve called “Krzemionki Opatowskie” was established by order of the Minister of Environmental Protection, Natural Resources, and Forestry on 27 June 1995.
Its geological structure and terrain morphology determine the specific nature of Krzemionki. The reserve is located at an altitude of 191.4–205.5 m above sea level and includes a belt of Upper Jurassic limestone outcrops with Neolithic flint mines. It consists of an archaeological reserve and surrounding forest and post-industrial areas with a total area of 378.81 ha. The reserve was established to preserve the sites of many rare and protected plant species for scientific and educational purposes, mainly associated with thermophile and calciphilous shrub and grassland plant communities.
From 1913 to the mid-1970s, the village of Krzemionki existed near the exploitation field. Part of the exploitation field and the adjacent areas were used as pastures and arable fields. Even today, in the southern part of the reserve, you can see the remains of buildings, orchards, and farmyards.
As a result of mining and industrial activity conducted in different periods of history (Neolithic mines and deforestation, pastoral and agricultural activity, limestone extraction at the beginning of the 20th and the end of the 20th century), a specific mosaic of natural habitats has developed in the area of today’s reserve. The presence of limestone bedrock and flint extracted and deposited on the surface for several thousand years and deforestation of the area led to the creation of a limestone substratum highly exposed to sunlight. The reserve has no watercourses, and the subsoil is highly permeable, making it a dry area. The only natural, periodic water reservoirs are several small karst sinkholes. The soil, water, and microclimate conditions are quite harsh. The conditions are favourable for species with specific habitat requirements, both xerothermic and mountainous, and those associated with oak-hornbeam and pine forests and thermophile oak forests.

A few dozen years ago, a significant part of the reserve was covered by protected and rare xerothermic grasslands. Currently, due to the ongoing ecological succession, they are in decline. Nevertheless, many species characteristic of grasslands still occur here. Ecological succession in the former xerothermic grasslands is heading towards developing subcontinental oak-hornbeam forest and continental pine forest with oak and birch. Part of the reserve is covered with thermophile oak forest. The reserve area is a unique place to study the natural succession of forest vegetation to agricultural parts, undisturbed by any interference. This is a dynamic process. The species composition has changed significantly over several decades and is still not formed.
In the “Krzemionki” Reserve area, there are 39 rare and protected plants, among which 11 species are strictly protected, 2 are partially protected, and the rest are rare plant species. The most interesting ones include the rose daphne (Daphne cneorum), ladybell (Adenophora liliifolia), snowdrup anemone (Anemone sylvestris), star gentian (Gentiana cruciata), lady’s-slipper orchid (Cypripedium calceolus), martagon lily (Lilium martagon), stemless carline thistle (Carlina acaulis), Pannonian Thistle (Cirsium pannonicum), and the red helleborine (Cephalanthera rubra).












Among the greatest curiosities of the invertebrate world of Krzemionki, we should mention rare and endangered species of butterflies: Duke of Burgundy (Hamearis lucina), green-underside blue (Glaucopsyche alexis), sloe hairstreak (Satyrium acaciae), and the solitary wasps (Scolia hirta); beetles: hermit beetle (Osmoderma eremita) and Darkling beetle (Neomida haemorrhoidalis) associated with primaeval forests; as well as the European mantis (Mantis religiosa) and the saddle-backed bush cricket (Ephippiger ephippiger), related to the great green bush-cricket (Tettigonia viridissima). A rare species of fly is found in Krzemionki: the soldier fly (Clitellaria ephippium).
Amphibians and reptiles are represented by several species, including the very rare and beautiful smooth snake (Coronella austriaca).
The bird world of the reserve is equally rich. There are 98 species (including vagrant species). Among the most interesting, rarest, and most endangered species are the collared flycatcher (Ficedula albicollis) and European pied flycatcher (Ficedula hypoleuca), stock dove (Columba oenas), and middle spotted woodpecker (Dendrocoptes medius). Interesting species include European nightjar (Caprimulgus europaeus), Eurasian hoopoe (Upupa epops), red crossbill (Loxia curvirostra), woodlark (Lullula arborea), red-backed shrike (Lanius collurio), and Eurasian woodcock (Scolopax rusticola). During migrations, golden eagles (Aquila chrysaetos) have been observed here. The Reserve is a place of frequent encounters with lesser spotted eagle (Clanga pomarina) and black stork (Ciconia nigra).
The nature reserve “Krzemionki Opatowskie” is a refuge for a significant number of mammals due to its large area and partial fencing. The largest species here is the moose (Alces alces). Red deer (Cervus elaphus) also occur here. Grey wolves (Canis lupus) sometimes appear. European badgers (Meles meles) and beech martens (Martes foina) live here. The European fat dormouse (Glis glis) deserves a mention among the smaller mammals. The Neolithic mines are the wintering grounds for 7 species of bats, including the greater mouse-eared bat (Myotis myotis).
The reserve area is currently the subject of interdisciplinary research. An inventory of habitats and plants, invertebrates, reptiles, amphibians, mammals, and birds is being conducted. Our knowledge of natural values changes and enriches every day.
In 2009, the area of the prehistoric mines in Krzemionki, located in the Kamienna River valley, was included in the Natura 2000 network under the name “Krzemionki Opatowskie” (PLH260024).