Krzemionki, also called Krzemionki Opatowskie, is a Neolithic and early Bronze Age site where people mined flint. This flint came from Upper Jurassic (Oxfordian) banded flint deposits located about eight kilometers northeast of the Polish city of Ostrowiec Świętokrzyski. It is one of the largest known prehistoric flint mining areas in Europe, along with Grime's Graves in England and Spiennes in Belgium.

Flint mining at Krzemionki began around 3900 BC and continued until about 1600 BC. During the Neolithic period, the Funnelbeaker culture used the mines to make tools, such as flint axeheads, which were transported up to 300 kilometers away. Later, the Globular Amphora Culture used the pits more heavily, expanding the reach of axehead distribution to about 500 kilometers.

Krzemionki is a Polish historic monument, officially recognized on October 16, 1994. The National Heritage Board of Poland oversees its protection. On July 6, 2019, the Krzemionki Prehistoric Striped Flint Mining Region was added to the UNESCO World Heritage List.

History of mining

The mining area is 4.5 kilometers long and 25 to 180 meters wide, covering 78.5 hectares. More than 4,000 mine shafts are known, with some reaching a depth of 9 meters. Access shafts range in diameter from 4 to 12 meters. Some shafts are connected by short horizontal passages called adits, which are 55 to 120 centimeters high and cover about 4.5 kilometers. Rare Neolithic pictures are engraved on the walls of some adits.

Flint from Krzemionki was mined from around 3000 to 1600 BCE by people of the Funnelbeaker culture, Globular Amphora culture, and Mierzanowice culture. These groups used hatchets to mine flint, which was mainly used to make axes and chisels. Many of these tools were traded as far as 660 kilometers away. The eastern group of the Globular Amphora culture is clearly different from the western group in central Germany, where flint was not used, but special battle axes were common. The main period of mining was between 2500 and 2000 BCE. Mining activity declined between 1800 and 1600 BCE.

In later centuries, the Krzemionki mining area was only visited occasionally. The village near the mines was first mentioned in historical records in 1509 and was owned by a man named Jakub from Szydłowiec. In the first half of the 20th century, the area’s many small limestone quarries were used to produce lime.

History of scientific investigations and tourism

The mines were found in 1922 by geologist Jan Samsonowicz. In 1923, archaeologist Stefan Krukowski began leading archaeological studies of the area. After World War II, Tadeusz Żurowski led the research team. He studied the Krzemionki mines, especially from 1958 to 1961. In 1967, the Krzemionki mines were made into an archaeological reserve. In 1995, they were also made into a natural reserve.

Small groups of visitors began exploring the Krzemionki mines in the late 1950s. Large-scale tourism started on June 11, 1985, with the opening of Tourist Route Number 1. A second underground route opened on June 10, 1990. An open-air archaeological museum was created in 1992. The underground tourist route is 465 meters long and reaches a depth of 11.5 meters at its deepest point.