Krzemionki holds one of Europe's largest prehistoric flint mine complexes. Mining started 3900 BC by Funnelbeaker culture. Lasted until 1600 BC. Globular Amphora culture expanded operations and trade to 500km. Over 4000 shafts up to 9m deep. Shafts 4-12m diameter with connecting adits 55-120cm high. Flint used for axes and chisels. Tools traded up to 660km. Eastern Globular Amphora group defined by Krzemionki flint unlike western group's battle axes. Peak exploitation 2500-2000 BC. Decline after 1800 BC. Discovered 1922 by Jan Samsonowicz. Archaeological digs since 1923. UNESCO World Heritage Site since 2019. Area 78.5 ha with 342.2 ha core zone. Tourist routes opened 1985 and 1990. Neolithic engravings on some walls. Mierzanowice culture also mined there.