Pavol Jackovič and his friends were hiking through the northern Tatra mountains when they stopped to rest on rocks 150 meters above the country’s largest and deepest alpine lake, Veľké Hincovo pleso.
Gobsmacked Jackovič told Slovakia state broadcaster RTV: “That was the moment when I saw something rising to the surface from the lake.
“It must have been something very big to see it from that height.
“My guess was that it must have been at least three to four meters long.”
Admitting the group had been too astonished to take a photo, he added: “The eyewitness testimony of three people cannot be disputed.
“Probably, if I were alone, I would have said I was dreaming.
“But we didn't dream this, that's for sure.”
Mountain rescuer and writer Jaroslav Švorc said: “They confirmed and literally swore that they had seen some strange creature, like a huge fish, but they couldn't identify it.”
The 53-meter lake, which is artificially stocked with trout, is located in an inhospitable environment and covered with ice up to 270 days a year.
Milan Štefánik from the nearby tourist resort on Popradské pleso lake said: “I believe that these guys saw it.
“I am now hearing various rumors that a marena whitefish may have grown to gigantic proportions.”
The mountain protection administration (TANAP) said that although it initially believed the hikers had seen a shoal of sturgeon, it has since dismissed that idea.
The organization’s Jozef Hybler said: “We have rejected the theory because sturgeon live in warmer waters and the altitude of 1,946 meters, where Hincovo pleso is located, is too high for it to survive.”
He added: “At the moment we are not planning any sonar or other survey of this lake.
“There is no relevant evidence to rely on yet.”
