An accomplished endurance athlete who competed in ultramarathons and listed summiting several of the world’s tallest mountains among his feats was found dead this week in Yosemite National Park in California, the National Park Service said.
The hiker, Fred Zalokar, had been missing since Saturday, according to park officials, who said his body was recovered by park rangers on Tuesday near the summit of Mount Clark, a granite peak that rises more than 11,500 feet.
The Park Service did not immediately say how Mr. Zalokar, 61, had died, but a longtime friend, Sean Crom, said in an interview on Thursday that Mr. Zalokar had fallen. An autopsy is not scheduled until next week, according to a representative for the Mariposa County sheriff and coroner.
Mr. Zalokar, who was from Reno, Nev., went on a day hike on Saturday using an off-trail route and did not return, park officials said. He was reported missing on Sunday.
Mr. Crom, who first met Mr. Zalokar about 35 years ago while training for a 100-mile ultramarathon, said that they had climbed mountains together all over the world and that his friend was fearless.
“Fred would be the one to climb up on the technical part and throw a rope down to the rest of us,” said Mr. Crom, who climbed Mount Aconcagua in Argentina, the highest point in the Americas, with Mr. Zalokar, and Mont Blanc on the border of France and Italy.
The family of Mr. Zalokar, who was a husband and father, said on Thursday that it was not prepared to comment.
His death set off an outpouring of tributes to Mr. Zalokar, who was well known in the spheres of competitive running and mountain climbing.
At age 55, Mr. Zalokar ran the New York City Marathon in 2 hours 43 minutes 10 seconds in 2015, finishing first in his age group, according to official records. In 2011, he finished the Boston Marathon in 2:34:52, the fastest time in the 50 to 54 age bracket.
According to his website, he was the first runner to win his age group in all six Abbott World Marathon Majors, which are in New York, Boston, Chicago, London, Berlin and Tokyo. He had also competed in marathons on every continent, including Antarctica, where, his website said, he finished first in February 1999 in just over 3:45.
“When I heard about the Antarctica Marathon in 1998, I thought, ‘Hey, I could do that!’” Mr. Zalokar said on his website.
He said that the marathon was more practical and cost less than trying to climb the Vinson Massif, the highest peak in Antarctica and one of the Seven Summits, the nickname for the tallest mountains on each continent.
According to his website, he had summited at least four of them — Aconcagua (South America), Denali (North America), Kilimanjaro (Africa) and Elbrus (Europe). A fifth, Kosciusko, is considered by some as the tallest mountain in Australia.
“He didn’t make it up Mount Everest, but he tried it,” Mr. Crom said.
Mr. Zalokar’s website is a cross between a scrapbook and a catalog of his feats. On one page is a list of the countries that he said he had visited, 137 in all, from Azerbaijan to Zimbabwe. There are photos of him rappelling down a granite mountain face, standing with arms raised on a sand dune in Namibia and, of course, running.
“He was very adventurous,” Mr. Crom said. “He’d kind of pick a goal and go after it hard.”
From ascending every mountain over 14,000 feet in California to exploring the tallest volcanoes in Mexico, Mr. Zalokar would check off the peaks that he had summited on his website. It’s known as “peak bagging,” said Mr. Crom, who explained that it was not unusual for Mr. Zalokar to hike on a mountain by himself.
“We don’t know yet if he made it to the top of the mountain,” he said of Mount Clark, noting that park rangers would most likely check a log book at the summit. “Fred always signs into the log book.”