Some of the times could qualify for big name marathons, some not nearly as fast - but when there are five runs in five days, it's a matter of endurance for runners at the peak of athletic ability and up into their 40s, 50s, 60s and even their late 70s.
Organizer Clint Burleson said the weather this past weekend was perfect, Belle Fourche is a perfect headquarters host - and the series will be back for a third run in the fall of 2015.
The Belle Fourche leg of the five-day, five-state, five-marathon Center of the Nation series literally started at the Center of the Nation monument park. The closed course followed the RiverWalk bike and walking path.
The series began last year with 210 runners. This year was down a bit to 160.
Burleson said part of the shorter turnout is because the first year always has greater appeal - and he added that the series concept has brought his Mainly Marathons operation into adding more similar multi-state running series.
Some of the appeal of the series concept is for runners to take a long weekend and run five courses in five states all in a row.
Some is a matter of how many marathons one can run.
Texas attorney Larry Macon has run more than 1,370 marathons in his career. The times may not be up to an Olympics standard, but imagine even walking 26 miles a day for five days in a row.
The CON series had runners from some 40 states, England, Australia and Portugal.
Weather helped the runners this year, Burleson said. Last year the 90-plus degree weather was a bit warm for a long run.
Two different towns were added to the five-state series this year. It began at Bowman, N.D., headed to the new Montana site at Baker, hit Belle Fourche and then turned to a new course at Sundance, Wyo., before heading to Chadron, Neb., to close the series.
"We will be back next year," Burleson said. "This is our biggest series of the year."
He added that the top male and top female endurance runners - folks who will run hundreds of marathons in a year's time - were at Belle Fourche.
"One hit 600 today," he said.
Times are listed, Burleson said, but that's not what wins trophies.
It's a matter of encouraging everyone to run half and full marathons and to enjoy the sport.
"We don't give awards for speed," he said. "There's 'caboose' for the slowest runners, first timers - and the fellow who is doing 600 today gets an award."
He grinned: "It's a matter of having fun and keeping healthy."
Sue Parrotte of Arlington, Va., runs in some and volunteers to help the program other days while her husband is running.
Burleson said the Belle Fourche based CON series is among the most popular.
He said the "fun bunch" of runners enjoy the community and buy fuel, meals, groceries and other supplies here.