Krizna Cave
   A chain of twenty two underground lakes of crystal clear water.
   http://www.kovinoplastika.si/gsk/krizna-jama/

Postojna Cave, Slovenia
   Official home page of this natural wonder.
   http://www.postojna-cave.com

Slovenian Tourist Board
   Official site including extensive information on tourism, accommodation, regions and news.
   http://www.slovenia-tourism.si