Environmental Geology

, Volume 54, Issue 4, pp 711–718 | Cite as

The largest karst cave discovered in a tunnel during motorway construction in Slovenia’s Classical Karst (Kras)

  • Martin KnezEmail author
  • Tadej Slabe
  • Stanka Šebela
  • Franci Gabrovšek
Original Article


Karst researchers of the Karst Research Institute ZRC SAZU are regularly consulted during the planning of Slovenia’s motorways and invited to observe and monitor construction in the karst areas. More than 350 caves have been discovered in the course of building 60 km of new motorways over the past decade. Access to the most important caves is preserved by concrete tubes closed with metal covers at the roadside. The largest cave system in a tunnel, named LC-S647, is almost entirely preserved. The protection of this cave will serve as a good example for the preservation of natural heritage in the future. Construction work for the motorway uncovered a high degree of karstification. In particular, the discovery of this cave in the Kastelec tunnel LC-S647 showed the existence of a major cave system in the geological and speleological past. A number of unconnected passages have also been found. Caves discovered during highway construction have brought new knowledge about the cavernosity and the geological history of this part of the karst.


Highway construction Karst Karst caves Classical Karst (Kras) Slovenia 



This research was conducted under the auspices of the project Karst phenomena along the Klanec-Srmin motorway section, funded by Motorway company in the Republic of Slovenia (DARS). The authors would like to thank Stanislav Glažar for providing Fig. 3.


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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Martin Knez
    • 1
    Email author
  • Tadej Slabe
    • 1
  • Stanka Šebela
    • 1
  • Franci Gabrovšek
    • 1
  1. 1.Karst Research InstituteScientific Research Centre of the Slovenian Academy of Sciences and ArtsPostojnaSlovenia

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