The Moab Alpine and Slickrock 50, also known as the MAS50, features a trail run through aspen groves on the La Sal Mountains before a descent to slickrock through the Sand Flats Recreation Area. [Courtesy photo]

Thirty-six ultra-runners will trek 50 miles along the western slopes of the La Sal Mountains to the slickrock desert below this coming Saturday, Sept. 14 in the Moab’s Alpine to Slickrock race. Also known as MAS50, the course crosses three mountain passes to arrive at the Slickrock bike trail within the Sand Flats Recreation Area.

The MAS50 is an ultra-marathon organized by Moab local Chris Martinez, owner/operator of 360 Moab Adventures, a trail running guiding company.

“The MAS50 was the first trail run event in Moab, and since then other trail running races events have been popping up since 2004,” Martinez said.

Martinez first put the race together in 2004 with the help of friends and fellow runners. He described the race as being “the best of both worlds of Moab, alpine and slickrock.” The course offers views of Arches and Canyonlands national parks and the Colorado River.

It was intentionally set for mid-September to coincide with the colorful changing of the leaves.

Martinez began thinking about designing races after running the Pacific Crest Trail 50 Trail Run.

Another runner asked him, “Why isn’t there an ultra-marathon in Moab?”

“A light went off in my head,” Martinez said.

Runners begin at 6 a.m. at 6400-foot elevation at Pack Creek. The goal is to finish by 8 p.m. at the Slickrock bike trail head. In between the start and finish lines are Geyser and Burro Passes, which both rise to heights of 11,000 feet, only to descend to the Slickrock trailhead at 4700 feet.

The variety of scenery and climate on the run attract runners from around the country.

“At mile twelve, it felt like a rainforest; everything was covered in fallen tree limbs and wildflowers. And the aspens were incredible,” said Richard Neslund of Louisville, Colo., who ran the race last year.

Ian Torrence placed first in last year’s trail run with a time of 10 hours and 30 minutes, making the race his 167th ultra-marathon and 51st win.

Martinez organizes three trail running events each year in Moab: The Red Hot 55K and 33K in February, the MAS50 in September, and the Amasa in April.

The Red Hot happens every President’s Weekend.

“It was voted the No. 1 race to do in the Rocky Mountain Region in Competitor Magazine this year,” Martinez said.

Martinez was inspired to design the Red Hot 55K and 33K race while running the Steel Bender trail with Torrence.

“It was a sunny wintery day and with the sun’s ray striking the snow-covered spires I immediately thought of hot embers glowing,” Martinez said. “I immediately envisioned a steady stream of runners experience the awe-inspiring views Ian and I had just experienced.”

The Amasa is held in the spring on the Amasa Back trail system in the Kane Creek area south of Moab.

“The Amasa is a great low key run that is growing every year,” Martinez said. “I started this event to try to get more locals to come out and trail run.”

The distances at the Amasa are 6.5mi, 9.5mi, 15.5mi.

“A lot shorter distances than Moab’s Alpine to Slickrock 50-mile and Moab Red Hot 55k/33k,” Martinez said.