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Premium Photo | Underground tourist train in postojna cave slovenia it is the secondlongest cave system in the country
![Diversity | Free Full-Text | Postojna-Planina Cave System in Slovenia, a Hotspot of Subterranean Biodiversity and a Cradle of Speleobiology Diversity | Free Full-Text | Postojna-Planina Cave System in Slovenia, a Hotspot of Subterranean Biodiversity and a Cradle of Speleobiology](https://www.mdpi.com/diversity/diversity-13-00271/article_deploy/html/images/diversity-13-00271-g002.png)
Diversity | Free Full-Text | Postojna-Planina Cave System in Slovenia, a Hotspot of Subterranean Biodiversity and a Cradle of Speleobiology
![Diversity | Free Full-Text | Postojna-Planina Cave System in Slovenia, a Hotspot of Subterranean Biodiversity and a Cradle of Speleobiology Diversity | Free Full-Text | Postojna-Planina Cave System in Slovenia, a Hotspot of Subterranean Biodiversity and a Cradle of Speleobiology](https://www.mdpi.com/diversity/diversity-13-00271/article_deploy/html/images/diversity-13-00271-g001.png)
Diversity | Free Full-Text | Postojna-Planina Cave System in Slovenia, a Hotspot of Subterranean Biodiversity and a Cradle of Speleobiology
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