In Mělník, a huge former underground quarry for sandstone has been discovered

Mělník - A former underground stone quarry, abandoned presumably after World War I, which no one knew about until now, was accidentally discovered in Mělník in the locality of Na Kroupovci. The city has sold the land above the quarry to private owners, and houses are set to be built there. The city leadership now wants to ensure that the construction is safe, said the mayor of the city, Ctirad Mikeš (ČSSD), to ČTK.
      The zoning plan for the locality of Na Kroupovci anticipates development; it is designated as a buildable area. "People bought the land in good faith, and we later discovered that there is a quarry underneath," stated the mayor. This was discovered when the city leadership began to work towards making the well-known quarry in Mělník - Vehlovice accessible. Experts searching in mining archives found that there is another mining operation in Mělník.
      According to the building law, builders must secure the foundations of the houses so that construction can proceed above the mining site. This poses a significant financial burden for the landowners. "We have therefore turned to the Ministry of Industry and Trade, which should undertake the remediation of the mining operation so that construction and activities above the quarry can continue," added Mikeš.
      There is also a road leading through the locality. According to Mikeš, the remediation of the stone quarry is estimated at four million crowns. The city wants to resolve the complicated situation to prevent potential problems in the future. "We cannot pretend that because nothing has happened in the past 70 years, nothing will ever happen," emphasized the mayor.
      The quarry was likely worked until around 1920. "The Sudeten owner was displaced in 1945, and no one among the people who live in the area today remembers the mining operation," added Mikeš.
      The underground of Vehlovice was created through the extraction of tuff. In the winter months, it serves as a refuge for certain species of bats, such as the lesser horseshoe bat. The largest chamber has an area comparable to that of a football field. The tuff was processed on-site into blocks. It is likely that mining there developed since the Romanesque period and that the tuff blocks in the Romanesque and Gothic architecture of Mělník come precisely from Vehlovice.