The 41-year-old, who's hoping to win the IBF, WBA and IBO heavyweight titles at Wembley Stadium, said that, like the mountain, he has been "there for a long time and will be there for a long time," per ESPN.
Klitschko's comments were perhaps goading Joshua for being relatively inexperienced compared with the Ukrainian, who has faced 68 opponents in 27 years of professional boxing. By comparison, Joshua has fought a grand total of 18 times.
"It was 27 years ago when I started [fighting as a professional] and I am still here," Klitschko said, per PA Sport, extending his Mount Everest comparison. He also took to Twitter to talk of his obsession with winning this month:
The fight is expected to be a "post-war record crowd" for a boxing match of 90,000 fans in London, making it arguably the most important match of either boxer's career. Klitschko, however, does not appear to be fazed, boasting that only four people have ever successfully "conquered" him in the ring.
"Four of them have made it out of a 21-year professional career," he said. "The rest didn't. Most didn't and the most amazing thing is I'm still here: they're not."
However, Klitschko also took the time to praise his upcoming opponent, commending Joshua's reserved attitude and eagerness to learn when visiting Klitschko's training camp in 2014.
"He impressed me with his attitude," he said. "He was very raw. I have to say the truth, but he was the Olympic champion, he carried himself well. He was in the background and learning. Sometimes you need to be quiet and just watch. He was observing everything."
A quiet respect for Joshua and self-confidence ahead of the fight at Wembley is a healthy mix for Klitschko, whose remarkable record in the ring is a daunting prospect for the British boxer.
Regardless of whether Klitschko is as difficult to conquer as Everest on April 29, this looks set to be a colossal fight between two giants of the sport.
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