Unskied Line #7: Lhotse Couloir

The highly exposed Lhotse Couloir, as viewed from the summit of Mount Everest in 2006. Jimmy Chin

[Ed's note: Don't miss the first, second, third, fourth, fifth, sixth, and seventh installments of our Unskied Lines series.]

Lhotse, the fourth-highest mountain on earth at 27,890 feet, is one of skiing's last great unclaimed prizes. It has never been skied from the summit; the closest anyone's come was Jamie Laidlaw's 2007 descent of the pencil couloir, which plunges 2,000 feet off the summit ridge. Due to a malfunction with his oxygen tank, he was forced to click into his skis approximately 800 feet from the top, commencing the descent alone and by headlamp.

Ever since then, Laidlaw, now 30, has ached for another shot at Lhotse. On Thursday, he left his hometown of McCall, Idaho, and returned to Nepal to finish what he started.

Laidlaw will be climbing and skiing with Kris Erickson of Livingston, Mont., the first American man to ski an 8,000-meter peak. Well-known alpinist and photographer Jimmy Chin had been set to join them, but pulled out of the trip after a close call with a massive avalanche in the Tetons last week. The North Face and Revo are the primary sponsors behind the two-month Lhotse expedition.

If all goes as planned, Laidlaw and Erickson will depart Kathmandu for the Khumbu Valley on Tuesday, April 12, and could make a push for the summit about a month later, Laidlaw said, after trekking to base camp, acclimatizing and evaluating conditions. Though they'll be able to scout the 5,000-foot Lhotse Face, which precedes the couloir, in all likelihood they'll enter the couloir blind to what kind of snow it contains.

"It's hard because the only way you can see the couloir would be to take a flight or to be standing on the south summit of Everest," Laidlaw said.

The couloir is the most common ascent route to the summit of Lhotse, but even so, it's only attempted by a handful of climbers each year. Part of that is due to the lure of Everest, which sits right next to Lhotse. The two mountains share a climbing route up to camp four, where the Lhotse track branches off and becomes much more difficult.

Speaking about the route in its entirety, starting with the west face, Laidlaw said: "It's probably 45 to 48 degrees for 5,000 feet, and then the couloir is 46, 47 degrees with some short bits that are in the low 50s."

Much of the route was blue ice when Laidlaw arrived at Everest Base Camp in 2007, but after a number of wet storms rolled through, the ski descent became more realistic. "If you're patient enough, the spring storms can put down an edgeable surface," said Laidlaw, who descended the couloir in breakable crust at 3 a.m.

He remains the only known person to have tried to ski Lhotse.

Of this year's trip, he said: "Whether it happens or not, it's one last attempt and I can put it to bed knowing that I've tried it twice."

You can follow the expedition here.