![Speleologists explore Malom lake inside Janos Molnar cave, one of the world's biggest thermal water caves, during a media visit to the newly discovered galleries of the cavern under the streets of Speleologists explore Malom lake inside Janos Molnar cave, one of the world's biggest thermal water caves, during a media visit to the newly discovered galleries of the cavern under the streets of](https://c8.alamy.com/comp/2D1RTJB/speleologists-explore-malom-lake-inside-janos-molnar-cave-one-of-the-worlds-biggest-thermal-water-caves-during-a-media-visit-to-the-newly-discovered-galleries-of-the-cavern-under-the-streets-of-budapest-november-18-2008-reuterslaszlo-balogh-hungary-2D1RTJB.jpg)
Speleologists explore Malom lake inside Janos Molnar cave, one of the world's biggest thermal water caves, during a media visit to the newly discovered galleries of the cavern under the streets of
![Cierna voda Slovakia.Feketenyék.2021.Potápanie.Diving.Underwater World.Búvárok Feketenyéken. - YouTube Cierna voda Slovakia.Feketenyék.2021.Potápanie.Diving.Underwater World.Búvárok Feketenyéken. - YouTube](https://i.ytimg.com/vi/e4QSuXGWN7k/hq720.jpg?sqp=-oaymwE7CK4FEIIDSFryq4qpAy0IARUAAAAAGAElAADIQj0AgKJD8AEB-AH-CYAC0AWKAgwIABABGBEgcigWMA8=&rs=AOn4CLDGZ8WWb13OvVR9qX5VUBm_VTMUmQ)
Cierna voda Slovakia.Feketenyék.2021.Potápanie.Diving.Underwater World.Búvárok Feketenyéken. - YouTube
![Speleologists explore Malom lake inside Janos Molnar cave, one of the world's biggest thermal water caves, during a media visit to the newly discovered galleries of the cavern under the streets of Speleologists explore Malom lake inside Janos Molnar cave, one of the world's biggest thermal water caves, during a media visit to the newly discovered galleries of the cavern under the streets of](https://c8.alamy.com/comp/2D16PEK/speleologists-explore-malom-lake-inside-janos-molnar-cave-one-of-the-worlds-biggest-thermal-water-caves-during-a-media-visit-to-the-newly-discovered-galleries-of-the-cavern-under-the-streets-of-budapest-november-18-2008-reuterslaszlo-balogh-hungary-2D16PEK.jpg)