Her head blood­ied and ban­daged, and her blond hair in a messy bun, Emi­ly Har­ring­ton pulled her­self over the last lip of El Cap­i­tan and into the clear, still night above Yosemite Nation­al Park, 21 hours 13 min­utes and 51 sec­onds after she began her ascent.

In her fourth attempt last Wednes­day night, Har­ring­ton became the fourth per­son, and the first woman, to scale El Cap­i­tan via the Gold­en Gate route in under 24 hours by free-climb­ing it — pulling her­self upward with her hands and feet and using ropes and oth­er gear only as a safe­ty net.

El Cap­i­tan, also known as El Cap, is a 3,000-foot-high gran­ite edi­fice that draws thou­sands of climbers to Yosemite each year. Climbers typ­i­cal­ly take around four to six days to reach the top, using a vari­ety of routes. Only a few elite climbers, Har­ring­ton now among them, have done it in less than a day.

Har­ring­ton, 34, of Tahoe City, Cal­i­for­nia, chose the Gold­en Gate route, which is divid­ed into 41 pitch­es, or sec­tions, because she had strug­gled to com­plete it in six days when she was first learn­ing to free-climb Yosemite’s monoliths.

Dur­ing a free-climb ascent, a climber goes up one pitch, then stops and is fol­lowed by a belay­er, a per­son attached to the oth­er end of the rope. If the climber falls, she returns to the bot­tom of the pitch and begins again.

As Har­ring­ton climbed, she said, she repeat­ed a mantra: “Slow is smooth, smooth is fast.”

“It was this giant rep­re­sen­ta­tion of every­thing I’ve worked for in climb­ing boiled down into one day,” she said in an inter­view. “There was a lot going on in my head, but at the same time I had this con­fi­dence deep down because I knew that I was more ready than I ever had been in my entire life.”

Har­ring­ton, who start­ed about 1:30 a.m., com­plet­ed the first two-thirds of the route with Alex Hon­nold, whose free-solo climb of El Cap, with­out ropes, was chron­i­cled in the doc­u­men­tary film “Free Solo.” They were attached by a rope — her on top, him at the bot­tom — mov­ing up the wall like a caterpillar.

For the last and most dif­fi­cult third, Harrington’s boyfriend, Adri­an Ballinger, a pro­fes­sion­al guide whom she met atop Mount Ever­est, swapped in as belay.

The climb went smooth­ly until she attempt­ed a dif­fi­cult pitch in the sun around noon Wednes­day. Her fin­gers were so slick with sweat that she slipped off, she said, so she rest­ed for 30 min­utes and tried again. She slipped off again, this time smack­ing her head against the wall as she swung on the rope. Sud­den­ly, she said, there was “blood every­where, spew­ing out from my head.”

She flashed back to a bru­tal fall she suf­fered last year while attempt­ing the same climb, one that sent her to a hos­pi­tal. But after check­ing her vital signs and ban­dag­ing her head, she put her hands on the rock once more.

“There was part of me that want­ed to give up and the oth­er part of me was like, ‘You owe it to your­self to try again,’ ” she said. “Then I just had one of those attempts where it was an out-of-body expe­ri­ence, like, ‘I can’t believe I’m still hold­ing on, I can’t believe I’m still hold­ing on,’ and then I was fin­ished with the pitch.”

Har­ring­ton, who grew up in Col­orado, has been climb­ing since she was 10. She is a five-time sport climb­ing U.S. nation­al cham­pi­on and a two-time North Amer­i­can cham­pi­on. She scaled Mount Ever­est and Mont Blanc in 2012, and Ama Dablam in 2013.

Free-climb­ing El Cap­i­tan, she said, requires strength, sta­mi­na, tech­ni­cal skill and the fit­ness to endure a day of exertion.

It’s unclear how many peo­ple in total have free-climbed El Cap­i­tan in under 24 hours, but the Amer­i­can Alpine Club, a climb­ing orga­ni­za­tion, esti­mates that only 15 to 25 climbers have pulled it off. The first to do so was Lynn Hill, whose scal­ing of El Cap in 1994, fol­low­ing the Nose route, remains one of the most famous ascents in rock climbing.

Free-climb­ing El Cap is still very much “a male-dom­i­nat­ed thing, despite the fact that Lynn was the first to do it,” Har­ring­ton said. “I always received so much advice from men, peo­ple telling me how I should do things, how I’m doing it wrong, but in the end I just decid­ed to do it any­way despite the fact that a lot of peo­ple felt that maybe I couldn’t or maybe I didn’t belong there.”

Steph Davis, who in 2004 became the sec­ond woman to free-climb El Cap­i­tan in under a day, using the Freerid­er route, said Har­ring­ton had achieved some­thing tru­ly remarkable.

“El Cap is so big that it becomes a real­ly big effort to free it in a day, and it takes a real­ly big com­mit­ment and a skill set beyond just the hard climb­ing it involves,” she said. “I think that’s why there’s a real­ly big time span between see­ing peo­ple do it.”

A lit­tle after 10:30 p.m., after hours of uncer­tain­ty and men­tal and phys­i­cal strain, Har­ring­ton used her chalk-caked hands to pull her­self onto the ledge at the top, where she and Ballinger were met by some of her clos­est friends. They popped a bot­tle of Cham­pagne and Har­ring­ton called her par­ents before the group began the two-hour descent to El Cap’s base.

“A lot of times, climb­ing achieve­ments, you don’t have a sta­di­um, you don’t have a bunch of peo­ple watch­ing on live tele­vi­sion,” she said. “It was this inti­mate moment in a real­ly spe­cial place.”