Who would come to the Twin Cities from Belgium or Zimbabwe or Australia just to take a really, really long walk?

Members of the slightly eccentric, worldwide community of people who like to walk briskly for hours on end. They make the journey because this is one of the few places in the country that holds a centurion event, a judged and sanctioned competition that gives an award for walking 100 miles in a day.

"If you talk with someone not in the racing lunatic fringe, they've not heard of it," said David Holmen, an accomplished ultradistance athlete from Eagan.

The challenge — which involves trudging laps day and night around a lake in a Twin Cities park — is no walk in the park. Those who have done it say it's harder than running 100 miles in 24 hours. In fact, it's such a rarely accomplished feat that more people have climbed Mount Everest or swum the English Channel than have earned a centurion walking badge.

To officially count as a centurion, there has to be a judge to certify that you were strictly walking. No running is allowed. Under the centurion rules, it's only been done successfully 94 times in the U.S. since 1878.

The 70th person to do it helped put Minnesota on the centurion map.

John Greene, a math professor at the University of Minnesota Duluth, turned to walking after a knee injury hampered his marathon running. When he learned that there was a walking category in the FANS ultra race event held every summer in the Twin Cities, he decided to see how far he could get in 24 hours.

FANS started in 1990 as a 24-hour ultra running event to benefit the FANS (Furthering Achievement through a Network of Support) college and career mentorship program of the Pillsbury United Communities organization.

Greene thought he could make it at least 78 miles, the record at the time for those walking the course. In 1999, his first try at the event, he clocked 80.4 miles in 24 hours, an experience he found to be "absolutely horrible." Halfway through, he couldn't bend his right knee. He suffered from blisters on his feet and aches all over.

"It was much, much harder than I thought it would be," Greene said.

Still, he was hooked on ultra walking, returning year after year to FANS, refining his training for an eventual attempt to get to 100 miles in a day.

"I could see myself getting better year by year," he said. In 2006, he did 93.6 miles.

By this time, other people were also trying for a 100-mile walk at FANS and had recruited Bruce Leasure, a Twin Cities racewalking judge for USA Track and Field, to judge the walk, making it an official centurion event.

In 2008, Greene was back again at FANS, power walking laps around Lake Nokomis in Minneapolis. That year, he had a sabbatical from teaching and was able to walk thousands of miles in training.

"I thought I was in really good shape," he said. He was 52 at the time. "I thought it was going to be easy."

Instead, it turned out to be a sort of slow-motion agony, full of fatigue and uncertainty and "was one of the most frustrating experiences in my life," he said.

Blisters made every step painful. He remembers the loneliness of slogging along by himself through the long night. His emotions swung from euphoria to depression while he did the math in his head, calculating whether he was on pace to make it. It was going to be close.

"I desperately wanted to do it," Greene said. "For the last eight hours, it felt like one misstep, one bad thing and the race was over. Eight hours of that is a long, long time."

When the 24-hour clock stopped for the 2008 race, Greene had walked 100.4 miles. He was the first person to become a centurion in the Twin Cities.

But he wasn't the last.

Out of the woodwork

After Greene became a centurion, the worldwide ultra walking community noticed. Racers started coming to the Twin Cities from places like the Netherlands, Belgium and Great Britain.

"Suddenly, FANS was on the map internationally," Holmen said.

The centurion rules, originally developed by the Great Britain Centurion organization, specifies that a centurion attempt must be watched by a judge to make sure the walker has at least one foot in contact with the ground at all times. Pacers, canes or walking sticks are not allowed.

The strict walking requirement is what makes walking a 100 miles in a day harder than running that distance, according to those who have done both. To travel 100 miles in 24 hours, you have to average 1 mile every 14 minutes and 24 seconds.

A runner can build up a lead by running faster than that and then take breaks by walking or even stopping. But it's hard to walk much faster than 13 or 14 minutes a mile for hours upon hours. To get to the 100-mile mark, you have to maintain a fairly aggressive pace almost nonstop around the clock.

"If you have to stop to change shoes or treat a blister, you really regret losing five minutes," said Holmen, who has run and walked 100-mile races. "As a walker, there's no way to make up the time. You kind of have just one gear."

Holmen has run nearly 125 miles in 24 hours, but he said "walking 100 miles is much, much tougher. You just don't have any margin for error. You can't make up any lost time."

"It's almost as much of a mental challenge as a physical challenge," said Rob Robertson, a centurion walker from Marietta, Okla. After 80 miles, it's a question of "how bad do you want to do it?" Robertson said. "Because it hurts."

After Greene got his centurion title at FANS, a couple from Australia flew to New York, bicycled to the Twin Cities and then together walked 105.7 miles at the event.

"They were tough people," Leasure said.

Holmen, who is Greene's brother-in-law and a veteran of more than 400 marathons and ultramarathons, walked 101 miles at FANS in 2018.

Badge of oddity

Robertson, the walker from Oklahoma, walked 100 miles at FANS in 2015 on his way to also getting centurion badges at events in Great Britain, Australia, New Zealand, South Africa and the Netherlands.

"It's a life-changing goal," said Robertson, owner of a smoked meats company who described himself as a "fat guy," when he took up walking at age 50. "I'm just a simple guy from Oklahoma."

Right now, the only place you can earn a centurion badge in the U.S. is at the Twin Cities FANS event and at a walking event held in late September in Owego, N.Y.

This year's FANS will start at 8 a.m. on Saturday with competitors doing laps around Snelling Lake at Fort Snelling State Park. Walkers from Belgium, the Isle of Man and Zimbabwe have signed up. Because of COVID concerns, all of them may not make it to the starting line.

But Steven Botma, a 22-year-old from Lansing, Ill., says he will be there shooting for 100 miles.

"I don't want to go back home without the badge," he said.

So will Jerry Young, a 64-year-old from Chautauqua, Ill. Young was a champion race walker as a youth and once tried to do 100 miles when he was 19. He quit at about 70 miles.

"It's always been a goal since then," Young said.

Greene will also be there. At 64, he said he doesn't have the speed to get 100 miles again. But he'd like to walk 73 miles, which would give him a lifetime total of 1,000 miles walked at FANS.

"I'm considered something of a celebrity there," he said. "It takes an odd personality to do it."

Richard Chin • 612-673-1775