Sotheby’s auctions the Rolex Oyster worn by Mercedes Gleitze during her 1927 English Channel swim on November 9th in Geneva, estimated at over 1 million CHF.
Some watches tell time. This one changed history. The Rolex Oyster that Mercedes Gleitze wore during her notorious 1927 swim across the English Channel is heading to Sotheby’s Geneva in November.
It’s only the second time in a century that the Mercedes Gleitze Rolex Oyster watch has gone up for sale.
Why This Watch Matters
This isn’t just another vintage Rolex. It’s the watch that proved waterproof wristwatches could actually work, and it launched the entire concept of sports endorsements as we know them.
Sotheby’s will auction it on 9 November 2025 at the Mandarin Oriental Hotel in Geneva, with an estimate of over 1 million CHF (roughly 1.3 million USD).
Sam Hines, Sotheby’s Global Chairman of Watches, puts it bluntly: “The 1927 vindication marked a turning point for Rolex. From that moment forward, Rolex aligned itself with the pursuits of adventurers, athletes and professionals operating in the most demanding environments on Earth. Mercedes Gleitze’s Channel crossing, nearly a century ago, laid the foundation for what would become a legacy of tool watches built for real-world performance.
The Oyster was instrumental in the transition from pocket to wristwatches, and the Mercedes Gleitze played an important role in this transition, rendering it one of the most significant wristwatches still in private hands.”
Hans Wilsdorf’s Ten-Year Obsession
Hans Wilsdorf spent a decade trying to build a waterproof wristwatch that people could actually use. He and his brother-in-law Alfred Davis founded Wilsdorf & Davis in 1905, and when they registered the Rolex trademark in 1915, Wilsdorf became fixated on one goal: making wristwatches replace pocket watches.
The problem was that “hermetic” watches existed, but they were basically useless. They had screw-down lids and bezels that made them too impractical for daily wear. Between 1922 and 1925, Rolex filed patent after patent for waterproof cases and crown systems. But the crown itself remained the weak point. How do you make it screw down securely while keeping the whole thing watertight?
Wilsdorf found his answer in 1925 when he bought patents from Swiss inventors Paul Perregaux and Georges Peret. Their screw-down crown system was good. He made it better by adding a clutch mechanism and a fully sealed case.
By 1926, Rolex had the Rolex Oyster, the first actually practical waterproof wristwatch with a hermetically sealed case and an easy-to-use screw-down crown. Wilsdorf applied for a patent in October 1926. Now he just needed to prove it worked.
Enter Mercedes Gleitze
Mercedes Gleitze was a secretary and typist in central London. She learned to swim in Brighton and got good enough at it that she started attempting increasingly ambitious swims across the Thames.
She first tried the English Channel in August 1922. At that point, only men had done it, starting with British Captain Matthew Webb in 1875, who took nearly 22 hours. Then everything changed on 6 August 1926 when Gertrude Ederle became the first woman to swim the Channel. Not only did she complete it, but she did it in 14 hours and 39 minutes, faster than any man before her.
Ederle was an American Olympic swimmer born in New York to German parents. Her record pushed Mercedes Gleitze to try again. She wanted to be the first British woman to conquer the Channel. Like Ederle, she decided to start from Cap Gris-Nez near Calais instead of the English coast.
Success, Then Scandal
On 7 October 1927, Mercedes Gleitze made it. Fifteen hours and fifteen minutes.
Three days later, her achievement got buried under controversy. A rival swimmer named Mona McLennan (also known as Dorothy Logan) claimed she’d also completed the crossing.
McLennan admitted to the press on 17 October that she’d lied, but the damage was done. Gleitze scheduled another swim for Friday, 21 October, to prove herself all over again.
They called it the ‘Vindication Swim.’
When a Failed Swim Created a Legend
The weather for the Vindication Swim was terrible. After 10 hours and 24 minutes in frigid, choppy water, Mercedes Gleitze had to give up.
But that “failure” ended up mattering more than her successful crossing.
The combination of Logan’s hoax and Gleitze’s celebrity turned the Vindication Swim into a national event. Hans Wilsdorf saw an opportunity. He contacted Gleitze and asked if she’d wear the new Oyster watch during her swim. She agreed, wearing it around her neck on a ribbon.
The partnership was managed by S. T. Garland Advertising Service, which would later merge with Saatchi & Saatchi. This was the birth of modern sports sponsorship, the template that every brand and athlete deal would follow for the next century.
The swim itself was a spectacle.
Press boats followed Gleitze’s progress. Friends, family, and even musicians came along to help keep her alert in the icy water. The Daily Mail chartered an aeroplane to capture aerial photographs, which ran on the front page the next day.
The First Real Product Test by an Athlete
Here’s what made this different from any marketing before it: Gleitze’s athletic achievement became proof of the product’s engineering.
A record-breaking endurance swimmer wearing a supposedly waterproof watch for over ten hours in the English Channel? That’s not an endorsement. That’s a stress test. And it worked.
Gleitze wrote a letter on 25 October 1927: “You will like to hear that the Rolex Oyster watch I carried on my Channel swim proved itself a reliable and accurate timekeeping companion even though it was subjected to complete immersion for 10h24 hours in seawater at a temperature not more than 58 and often as low as 51. This is to say nothing about the sustained buffeting it must have received. Not even the quick change to the high temperature of the boat cabin when I was lifted from the water seemed to affect the even tenor of its movement. The newspaper man was astonished, and I, of course, am delighted with it.”
Rolex called her a “testimonee” and built their entire campaign around “the watch that defied the Channel.” They published a full-page ad in the Daily Mail on 24 November 1927, celebrating that the Rolex Oyster “kept time despite being immersed in water for over ten hours.”
A Real Relationship
Mercedes Gleitze wore only her original Oyster watch for the rest of her life. Rolex offered her other models. She said no. She wanted to keep wearing her “companion,” the watch that had been through the Channel with her. When it needed maintenance, she’d send it back to Rolex.
The watch became the centrepiece of Rolex’s 50th anniversary celebration of the Oyster in 1976. It appeared at an exhibition at the Greenwich Observatory, timed to coincide with the announcement of the Rolex Award for Enterprise. Rolex has honoured Gleitze’s contribution consistently, even after her death in 1981.
What Makes This Watch So Special
The watch was probably made in late 1926, before the winding crown patent was finalised in early 1927. It has “patent applied for” inscribed on the case back. It’s made of 9-carat yellow gold.
Only a handful of pre-patent Rolex Oyster watches have ever appeared on the market. This one isn’t just rare. It’s arguably the most important watch in Rolex’s history. The company certainly thinks so; they’ve referenced the Vindication Swim for nearly 100 years as the moment everything changed, associating it with “the debut of the Rolex Oyster and its triumphant march worldwide.”
Two Parallel Stories
Mercedes Gleitze needed five years and nine attempts (including the Vindication Swim) to become the first British woman to swim the Channel. Rolex needed over a decade to create a reliable, practical, waterproof wristwatch.
Both Wilsdorf and Gleitze had German roots. He was born in Germany but lived in London. She was of German descent but British-born in Brighton. They shared a cultural background and a language. More importantly, they shared something else: they were both too stubborn to quit.
The Auction
This is the second time in a century the Mercedes Gleitze Rolex Oyster has been offered for sale, and the first time in 25 years. The estimate of over 1 million CHF isn’t just about the watch being rare or old.
It’s about what this watch represents: the moment Rolex became a major player through actual innovation, the shift from pocket watches to wristwatches, and the beginning of modern sports sponsorship with Gleitze as Rolex’s first brand ambassador.
Sam Hines is right when he calls it “one of the most significant wristwatches still in private hands.” This November in Geneva, someone will get the chance to own a piece of that history, not just a watch, but the moment when human endurance, engineering, and marketing came together and changed an entire industry.
*Images: Sotheby’s
