The site is a steep grey cliff that stands over the river Neretva right in front of the public beach in Konjic, a small town 60 kilometres (34 miles) southwest of capital Sarajevo.
The river runs shallow here except for one "hole" -- a pool only two metres (six feet) in diameter and two metres deep surrounded by jagged rocks, a potential death trap under the striking green water.
It is known as the "Kazan" or "pot," where young Konjic men have proved their courage for decades.
Word spread, however, and in the last 16 years it has become an annual "must" for the best divers in the Balkans.
Konjic's 18-meter (59 feet) cliff is far from the tallest in high diving, a discipline only admitted into official competition for the first time this July at the World Aquatic Championships in Barcelona.
But here, there is no room for error as the high diver aims for the small "hole" in otherwise knee-deep waters.
"The flight takes one to two seconds. A man is not a bird, and if we make a mistake we have no time to correct it," says Karalic.
The greying 55-year-old with short-cropped hair knows better than most. A tattoo on his chest of a man plunging head-first in a "swallow", or "swan" dive commemorates his first successful "leap of death" in 2001, a distinction few can claim.
-- 'More the mind, than muscles' --
While Konjic's classic high dive is made from 18 meters, those attempting the "leap of death" must climb 25 metres up the cliff before plunging into the "hole". And there are not too many divers who dare.
The Konjic competition has no international standing and the jumpers' only reward is a medal for bravery.
And despite the danger, no one has ever died. Locals remember only one accident years ago and even that was not serious, they say, because "only the best divers" come to Konjic.
At this year's event, Karalic, nowadays a referee, took his place alongside six other judges on a beach platform facing the cliff.
Sixteen divers from Bosnia, neighbouring Serbia and Montenegro, competed in two series of jumps, including 25-year old local diver Danko Dangbic, the Konjic champion for the last three years.
Hundreds of spectators applauded and shouted but when Dangbic reached the diving point, all went silent.
He raised his left hand to signal he was ready, focused on the "pot" below, spread his arms then dived. Seconds later, his head bobbed out of the cold water looking straight at the judges. Yes, his dive was perfect.
"It's more the mind then the muscles," he says. "It's the dive that requires concentration and perfect fitness, one cannot afford any mistakes"
His advice to future divers: "Determination and courage are crucial."
"Even the best possible physical fitness cannot help the jump if you are not brave," he says.
Dino Bajric, 24, this year's second-place winner sports a shiny silver medal around his neck and readily admits that it is the adrenaline rush that draws him to high diving.
"It is the challenge, the height, the freedom we feel in the air. These few seconds are indescribable."
"I feel as free as a bird. The space belongs to you during the flight, even if this feeling lasts only briefly, until you hit the water," he says.
"Then it really hurts."