Rolex has been called “the only watch that matters.” And that’s an opinion held not only by those people — like mountain climbers and deep-sea divers — who need a reliable and durable timepiece, but by investors. Handmade in the Swiss tradition using the finest materials available, a Rolex is among those rarest of things — a manufactured item that can actually appreciate in value as it ages.

But although Rolex is a household word worldwide, there are more than a few things people don’t know about the brand. And, to be sure, Rolex wouldn’t mind keeping it that way. The privately held company is well known for its discrete manner (and downright secrecy) with its inner workings. But here are a few things even collectors might not know:

1. Rolex Might Be the Pride of Switzerland, But it Started in London

The company didn’t start out making watches, but assembling them. Back in 1905, 24-year-old Bavarian immigrant Hans Wilsdorf and his English brother in law Alfred Davis started a company in London that imported Swiss movements and placed them in English watch bodies. They would them sell them to jewellers, who would put their own logos on the face. It wasn’t until 1908 that the guys decided to make their own watch, and opened an office Switzerland because that’s where the skilled watch makers were. Rolex’s headquarters finally left London for Geneva in 1919 because the post-World War I taxes on exports, gold and silver in Britain were astronomical, and crippled their ability to make any profits no matter how good their product.

2. Nobody is Exactly Sure What ‘Rolex’ Means

There’s an apocryphal story that Rolex comes from the French phrase for exquisite clockwork (horlogerie exquise, the H is silent), but neither the company nor its founders have commented on it. But Wilsdorf did admit that the name was picked because he wanted a word that was short and looked good on a watch face, and could be pronounced in any language. He’s also on record as saying he thought it sounded a bit like a watch being wound, but we think that’s a bit of a stretch.

3. World War II Prisoners Made Rolex a Desirable Brand

Flyers in Britain’s Royal Air Force hated their standard-issue watches, and many of them replaced them with Rolexes, which had earned a reputation as being both accurate and durable. When Wilsdorf found out that the Nazis took the watches of flyers who had been shot down and taken prisoner, he offered to replace any Rolexes lost by British prisoners based only on their word. American prisoners, held in the same camps, heard about the deal and were just as impressed with Wilsdorf’s confidence that the Nazis would lose as they were with his watches, and the brand became a status symbol among both British and American aircrews (as well as Canadian, Australian, New Zealander, South African and other Allied prisoners).

4. A Rolex Made the Great Escape Possible

One of those British prisoners, Corporal Clive Nutting, ordered a replacement Rolex Oyster 3525. He was answered personally by Wilsdorf, who was impressed that a non-officer would have such an impressive watch when most of the others of his rank were more interested in the cheaper, snazzier Speed King. The watch was delivered to Nutting at the prison camp, Stalag Luft III, with a personal note from Wilsdorf that declined Nutting’s offer to pay for the replacement and an apology that it took the company so long to get it to him. Nutting then used the Oyster 3525 to time the movements of the Nazi guards so that his fellow prisoners could evade them in what became known as the Great Escape. When the Steve McQueen film about the incident was made in 1963, Nutting hired as a consultant.

5. Rolexes Kept Ticking at the Top of the World and the Bottom of the Ocean

After the war, Rolex enjoyed even more prestige. In 1953, the men of the British Himalaya Expedition led by Sir Edmund Hillary were the first recorded humans to reach the summit of Mount Everest. All the principals in the expedition were wearing Rolex Oyster Perpetuals, and none of their watches broke down or even lost a second, despite the rigors of the climb. In 1960, the U.S. Navy’s bathyscaphe Trieste dove 35,798 feet down (that’s almost 8,000 feet deeper than Everest is high) to the deepest part of the Mariana Trench. Some sailors attached a Rolex to the outside, and were shocked to find that it still ran without losing a second, despite enduring pressures of 14,000 pounds per square inch.

6. A Rolex Once Helped Solve a Murder

Albert Walker Johnson was a high-school dropout and scam artist from Paris, Canada, who bilked 70 clients out of $3.2 million through a mortgage and investment scam. Wanted by Canadian police, he fled to England with one of his three daughters. He started a new investment business with another Canadian ex-pat named Ronald Joseph Platt. When Platt moved back to Canada, Johnson assumed his identity (with his 15-year-old daughter posing as his wife!) to avoid Interpol. But when Platt returned to England in 1996, Johnson decided to kill him. He would have gotten away with it too, if he was smart enough to take off Platt’s Rolex before dumping him in the English Channel. After two weeks in the water, the only identifiable thing was his still-ticking Rolex. Through service records, the police identified the body as Platt’s, and it didn’t take long to track down Walker.

7. Your Fake Rolex Isn’t Fooling Anyone

We once interviewed a Canadian stripper for another (very different) story, and she told us that she and all of her colleagues had been trained to recognize a fake Rolex in the crowd from the stage. “It’s easy,” she told us. The first thing they spot is the second hand. Rolexes, which are mechanical, have second hands that gracefully sweep the dial, while fakes, which are electronic, have second hands that that tick every second individually. Other cues, she told us, involve quality of materials, machining and design. Perhaps more obvious, she pointed out, is who’s wearing it. If you’re wearing Keds and an I’m-with-stupid T-shirt, that’s probably not a real Rolex on your wrist.

8. Rolex is a Charity … Maybe

When Wilsdorf’s wife, Doris Kuhlmann-Wilsdorf, died in 1944, he founded the Hans Wilsdorf Foundation, which he registered as a charitable organization. Later, he transferred all ownership shares of Rolex to the foundation with detailed instructions on how to handle the finances. Under Swiss law, no charities pay any taxes, but private charities have no requirement to reveal who they give to, or how much. The company says it likes to keep its donations completely anonymous, and no organization has ever acknowledged it has received support from the foundation.

9. Rolex Might Have Lost Millions to Bernie Madoff

In 2008, the watch world was stunned when Hans Wilsdorf Foundation CEO Patrick Heiniger stepped down “for personal reasons.” He and his father, Andre, had run the organization since Wilsdorf’s death in 1960 and there were no warning signs that their dynasty was about to end. Almost immediately, the European media started running stories claiming that the foundation had been scammed out of the equivalent of $900,000 by Bernie Madoff. After he was sentenced to 150 years for stealing more than $30 billion, Madoff’s own Rolex collection was auctioned off to help aid his victims, which included Kevin Bacon, Uma Thurman, Steven Spielberg and John Malkovich.

10. Rolex Takes Its Metal Very Seriously

While other stainless steel watches are made with a grade known as 316L, Rolex uses a much more expensive grade called 904L, which features higher levels of nickel and chromium. Not only is it more expensive to buy, it’s also much harder to machine, which required Rolex to have to upgrade most of its equipment at a hefty investment. The payoff, they say, is a much better resistance to pitting — a real problem for salt water divers. They also claim that the 904L holds a polish much better than other steels — which makes sense, considering the higher levels of nickel and chromium. And, if nothing else, it’s something to brag about. Oh, and also they have a foundry on their site for making their own gold and platinum.

11. Every Single Rolex is Pressure-Tested Before Leaving the Plant

Every Rolex is placed in a sensitive air-pressure chamber to determine if there are any air leaks in the case. All dive-rated Rolexes are then placed in a tank in which they are water-pressure tested to the equivalent of 300 meters (about 1,000 feet) deep. They are then subjected to a condensation test in which a drop of water is placed on the crystal of a heated watch. If a medical-grade optical sensor finds any condensation, the watch is scrapped. Deep-sea rated Rolexes are subjected to one final test in which they are subjected to the same kind of pressure they would face 12,000 meters (about 39,000 feet) below the surface of the ocean, even though the deepest spot in any ocean is just 10,911 meters down. But a Rolex has already been there.

12. Believe It or Not, Every Rolex is still Hand-Made

There’s a scene in the great British TV series Chef! in which a small-town reporter informs the chef that she “knows how it goes” and that all restaurants just microwave food prepared in some factory. As much as he tries, the outraged chef (played by veteran comic Lenny Henry) can’t shake her of that delusion. It’s kind of that way with Rolex, although few believe it, every watch is still painstakingly made by hand in Switzerland, with the hands placed on by a real human. There are, of course, machines involved with mundane tasks like sorting screws, but the important stuff is all done by Swiss fingers.