ADAMS — A ski race that started in 1934 is once again returning to Mount Greylock.

The Thunderbolt Ski Race, a nationally competitive event sanctioned by the U.S. Ski Mountaineering Association, is set for Saturday. Similar competitions were held in 2014 and 2015, and before that, more locally oriented revivals of the historical "down mountain" race took place in 2010, 2011 and 2014, before their discontinuation.

Bad weather always has been a factor, and it has caused cancellations. But, this year, the weather seems to be cooperating.

Since the previous run, in 2015, "the sport has become almost unrecognizable over the intervening years," said Jonathan Shefftz, director of the seven-venue NE Rando Race Series and treasurer of the USSMA.

Shefftz took third in the 2015 race that he also directed, yet he expects a struggle to place even in the top 20 this time, based on the highly competitive fields in other races this season, with racers traveling from 10 states and Canadian provinces.

Racers will earn national points under the ranking system of the USSMA.

After a mass start down in Greylock Glen at the gazebo, racers will ski uphill on climbing skins, interrupted partway up for a transition to steep hiking. Racers then will descend 2,000 feet of entirely ungroomed terrain. The total run up and down is about 6.3 miles. That's just one lap.

Then they'll do it all again. And again.

Once the racers reach the summit — it's a climb that takes at least 50 minutes for the fastest — the trail down begins at the Thunderbolt Shelter near the summit. They stop near the shelter to shed their skins and start the downhill run, which takes an additional 10 minutes or so.

More sensible participants have the option of skipping the hiking section, with only one or two laps.

Spectators are welcome, with viewing areas of the race from the Greylock Glen gazebo.

Race details are available at

ThunderFest, a celebration in honor of the Thunderbolt Ski Race and winter in the Berkshires, has, in the past, been scheduled to follow the race, but this year it will happen two weeks later, on March 7. It features food vendors from local eateries, local craft beers and wines, a chowder cook-off and tours of the Thunderbolt Ski Museum.