A Colorado woman who beat breast cancer a year ago set a world record as the first person to ever swim across the English Channel four times non-stop — an amazing feat that took more than 54 hours, according to a new report.

Sara Thomas, 37, of Colorado, began the challenge in the wee hours of the morning Sunday and completed it around 6:30 a.m. Tuesday, the BBC reported. She swam from England to France and back — twice.

The open water ultra marathon swimmer, who completed her cancer treatment last year, told the outlet that she was swimming for “all the survivors out there.”

“I just can’t believe we did it,” she said as she came ashore. “I’m really just pretty numb. There [were] a lot of people on the beach to meet me and wish me well and it was really nice of them, but I feel just mostly stunned.”

The entire swim should have been a total of about 80 miles, but the tidal pulls in the Channel increased the distance by more than 60 percent — meaning that Thomas swam a total of nearly 130 miles, according to the report.

Four swimmers have previously crossed the Channel three times without stopping — but Thomas was the first to ever complete the fourth go-around.

“Extraordinary, amazing, super-human!!!” swimmer Lewis Pugh tweeted of the feat. “Just when we think we’ve reached the limit of human endurance, someone shatters the records.”

Thomas told the BBC that there were challenges at every turn.

“Coming back from France the last time was definitely hard,” she said. “It took forever and the current pushed me all over. I got stung in the face by a jellyfish. [The water] wasn’t as cold as I thought it might be but it was still chilly.”

Thomas’ proud mom, Becky Baxter, told BBC Radio 4 that her daughter was a “freak of nature” but did have “a lot of trouble with stomach ache” on this trip.

“I’ve been on a lot of her trips,” Baxter said. “This was by far the scariest.”

Thomas’ supporters told the BBC that she “used the swimming as her means of coping with the [breast cancer] treatment.”

She only wore a cap, goggles and a swimsuit during the journey, as the Channel Swimming and Piloting Federation rules dictate.

Now that her record-smashing excursion is complete, she just wants to get some rest, she told the outlet.

“I’m pretty tired right now,” she said.