Ben Laster of Kalispell decided to go for a run Tuesday — a really big run — across the Bob Marshall Wilderness from north to south.

And he did it, covering 75 miles from the Meadow Creek Gorge to the North Fork Blackfoot River trailhead in 15 hours.

“I never stopped for more than five minutes. It was pretty much 15 hours of running,” Laster said Wednesday. “I was feeling kind of rough at the end. But not as bad as I thought I would be feeling.”

Laster, 29, works as a wilderness instructor for the Wilderness Treatment Center, which counsels troubled youths by exposing them to outdoor experiences.  

“I’ve done a few trips on the length of the Bob going north to south,” he said, adding that last year he started pondering the possibility of running the distance.

He started training in spring 2011, but because of nagging injuries, he wasn’t able to make the attempt. This year, he resumed training not knowing if the opportunity would arise.

“I knew I had to be running a minimum of 100 miles a week to even be able to think about it,” Laster said of his training regimen. “I was mostly doing a lot of trail running.”

Laster ran to Holland Peak, Swan Peak and most of the peaks in the Jewel Basin Hiking Area.

Then last week, while on a work-related trip in the South Fork Flathead River drainage, he decided to stay and give it a shot largely because he was feeling healthy enough.

“I’ve been pretty rough on my body. When my body is feeling good enough to do it, that’s another thing,” he said.

He also had to consider that fires in the wilderness could thwart an attempt if he waited longer.

“It looks like the Bob is starting to burn up, so I figured I better get through there,” he said.

Laster left the Meadow Creek Gorge at 4:30 a.m. Tuesday, running with a headlamp, a light wind jacket, electrolyte fluids to mix with his water, about 3,500 calories in Hammer Nutrition gels and nutrition bars, a lighter and extra socks.

He was a bit nervous about not having any type of food.

“It was the first time I was not reliant on whole food products and using just supplements,” he said. “It worked pretty well for me.”

The run took him down the east-side trail along the South Fork Flathead River to the Forest Service’s Big Prairie administrative site, where he stopped briefly to inquire about fire activity.

Then it was on to Flat Iron Mountain and across the Dry Fork Divide into the Scapegoat Wilderness and the Danaher Basin. The last 20 miles took him down the Dry Fork drainage and the North Fork Backfoot drainage.

Laster’s father was waiting for him at the trailhead with specific instructions not to seek help unless Laster failed to show up by 10 a.m. Wednesday.

“I knew there was a strong possibility that I might spend the night out there,” he said.

While Laster expected to be finished by 5 p.m., he ended up arriving at the trailhead at 7:30 p.m.

“I could have done it in 14 hours if it hadn’t been so hot,” he said.

Laster expected to be feeling pretty beat up after such an arduous journey but that hasn’t been the case.

“I actually feel pretty good after this,”  he said.

Reporter Jim Mann may be reached at 758-4407 or by email at jmann@dailyinterlake.com.