Exclusive | running up the vessel — four times — is the hottest new workout class

For tourists from around the world, the Vessel in Hudson Yards is a main attraction. They pay $10 a visit to climb to the top of the 16-story structure —which features 2,500 steps across 154

zig-zagging flights of stairs — and take in views of the city from 80 different landings. But for some local New Yorkers, the Vessel is just a huge piece of gym equipment. A just-launched

Equinox workout class has fitness freaks paying $55 to run up and down the honeycomb-shaped structure four times in 45-minutes and complete a grueling upper body strength workout at the top.

It’s no walk in the park. “It was more challenging than I thought it would be,” said Edgar Irizarry, 32, who works in tech, lives on the Upper West Side and did the class Tuesday morning.

“You think you are full of energy but then when you start getting closer to the top your legs just start hurting and feel really heavy and you still have two flights to go.” The classes take

place on Tuesday at 7 a.m. — for Equinox members only — and Thursday at 7 a.m. and 8 a.m. for the general public. Reservations must be made in advance. EXPLORE MORE Andrew Slane, one of the

instructors, said the class is even difficult for those already in good shape. “It’s very humbling,” he told The Post. “Many of the people taking the class run marathons and they were like,

‘This is hard.’” Christopher Vo, Director of Group Fitness Programming for Equinox, said it’s uniquely challenging because of the climbing aspect, which strengthens the glutes and legs. “A

lot of times when we are in a group fitness environment we are able to do things front to back or side to side but rarely do we get to go vertical,” said Vo. “It’s also a great

cardiovascular workout.” Equinox has been wanting to do a class at the Vessel since it reopened last October, following a three-year closure necessitated by a string of suicides. Vo said

it’s a truly unique fitness venue. “To be in it and have the structure swirl around you, it’s really special,” said Vo. The class, which has 20 to 25 people, starts with a stretching session

at the base. Then participants rum up the Vessel, back down, and up again. At the top they do upper body resistance movement with arm bands for about 10 minutes, before running down again

and doing more exercises, such as mountain climbers and planks, at the base. Then they repeat the entire process — or at least some do. “Some of the runners come down and never go back up,”

said someone who works at the Vessel and has observed early classes. Shahar Ifrah, 24, who lives in the city and works at the Israeli consulate, said one of the advantages of the class is

that you get to be at the Vessel hours before it opens to the public at 10 a.m. “It was crazy intense, amazing, and so much fun to get to experience this without any tourists around,” said

Ifrah, who participated in Tuesday’s class. “I absolutely want to do it again as many times as I can sign up.” Another advantage: she recorded herself running up the structure on her phone.

“I’m definitely going to post these videos,” she said. “Everyone is going to see that I did this.” But she had her limits. At the end of the class the instructors wanted to take a group

photo back at the top of the Vessel. Although they told the group they could walk, not run, even that seemed like a stretch. Ifrah asked, “Isn’t the elevator working?”