A woman who was treated for breast cancer a year ago has become the first person to swim across the English Channel four times non-stop.
Sarah Thomas, 37, began the epic challenge in the early hours of Sunday and finished after more than 54 hours.
Ms Thomas - who completed her treatment in 2018 - dedicated her swim to "all the survivors out there".
The swim was due to be about 80 miles but because of strong tides Ms Thomas ended up swimming closer to 130 miles.
Ms Thomas, from Colorado in the United States, completed the final leg on Tuesday at about 06:30 BST.
Speaking to the BBC after she came ashore at Dover, the open water ultra marathon swimmer said: "I just can't believe we did it. I'm really just pretty numb.
"There was 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."
She said she planned to sleep for the rest of the day, adding: "I'm pretty tired right now."
Swimmer Lewis Pugh said in a tweet: "Just when we think we've reached the limit of human endurance, someone shatters the records."
Extraordinary, amazing, super-human!!! Just when we think we’ve reached the limit of human endurance, someone shatters the records. Huge congratulations to Sarah Thomas on swimming the English Channel 4x continuously!!! 🏴🏊♀️🇫🇷 🏊♀️🏴🏊♀️🇫🇷🏊♀️🏴 pic.twitter.com/kOa9QlereH— Lewis Pugh (@LewisPugh) September 17, 2019
Ms Thomas's mother Becky Baxter told BBC Radio 4: "I've been on a lot of her trips. This was by far the scariest."
She said her daughter was a "freak of nature" but did have "a lot of trouble with stomach ache" on this trip.
Last year Ms Thomas had treatment for breast cancer and her support team said she "used the swimming as her means of coping with the treatment".
Elaine Howley, a member of Ms Thomas's support team, said the swimmer had returned to her accommodation near Folkestone with her family to sleep and recuperate.
She described her friend's achievement as "unfathomable, super human, just extraordinary".
"She has pushed out the boundaries of the sport of marathon swimming," she added.
What inspired the marathon swim?
Experienced swimmer Ms Thomas completed her first open-water event in 2007. She first swam across the Channel in 2012 and then again in 2016.
But that clearly wasn't far enough.
Speaking to film-maker Jon Washer, she said: "As I was doing 20 mile swims, it occurred to me that I could do more and I wanted to see what that more was."
In August 2017, she swam 104.6 miles in Lake Champlain on the US/Canada border, but was later was diagnosed with cancer.
Ms Thomas completed treatment for breast cancer in summer 2018 and dedicated her record-breaking Channel swim to other survivors.
How far did she swim?
Ms Thomas swam from England to France and back - twice - in just over 54 hours.
It should have been a total distance of about 80 miles (129 km) but the tidal pulls in the Channel increased the distance by more than 60%, meaning she ended up swimming nearly 130 miles (209 km).
Only four swimmers have previously crossed the Channel three times without stopping.
Before Ms Thomas no-one had ever completed a fourth leg.
Author and broadcaster Charlie Connelly has described her achievement as "one of the greatest feats of mental and physical endurance in human history", while official observer Kevin Murphy said she had "tested the limits of endurance".
What were the challenges?
Ms Thomas said dealing with the current was extremely tough as it was constantly pushing her off-course. And she was stung by a jellyfish.
But the worst thing was "dealing with the salt water... it really hurts your throat, your mouth and your tongue", she said.
Ms Thomas added: "Every length had something that was really hard about it.
"Coming back from France the last time was definitely hard. 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."
She also abided by the Channel Swimming and Piloting Federation rules when completing the crossing - so was only permitted to wear a cap, goggles, and a swimsuit.
How did she eat and drink - and stay awake?
For nutrition, Ms Thomas relied on a protein recovery drink mixed with electrolytes and a little bit of caffeine to help offset sleepiness.
Her mother said: "It is tied to a rope and we get her attention every 30 minutes and throw it to her."
She celebrated entering the record books and making dry land, with champagne and chocolates.
Congratulations to Sarah Thomas for successfully completing a 4-way historic crossing of the English Channel. An absolute legend! We'll have official confirmation of times shortly (I assume everyone needs a good sleep after that!)— CS&PF (@csandpf) September 17, 2019