French author Jules Verne has thrilled generations of readers with his novel “Twenty Thousand Leagues Under the Sea” published in 1870. The adventures of Captain Nemo navigating the seas in his underwater vessel the Nautilus are of course imaginary, but within those tales, Verne foresaw many features of today’s submarines. He also sensed great depths, in fact, the greatest depth of all.

While in the Western Pacific Ocean, Captain Nemo’s Nautilus circles around an area that includes the Mariana Islands and Guam. What Verne could not have known at the time is that beneath lies a series of ocean trenches, and in particular one that is crescent-shaped and measures 2,250 km in length and 69 km wide. Its depth is so great the tip of Mount Everest standing upright in it would still be 2,100 meters below sea level!

It was only in 1875 that details of this, the Mariana Trench, became known, during the British Royal Navy expeditions from 1872 to 1876. The crew of the HMS Challenger sounded it and discovered its depth of 10,935 meters, an enormous increase over our average oceans’ depth of 3,682 meters. The deepest point, at the southern end of the Mariana Trench, was accordingly named Challenger Deep.

Jules Verne would have loved what follows. He would have had to wait until 1960 to see the first manned descent into Challenger Deep, to 10,916 meters, when Swiss Oceanographer Jacques Piccard and US Navy Lieutenant Don Walsh touched the bottom in the Trieste, a submersible sphere specially designed to withstand extreme pressure. As an indication, at a depth of 11,000 meters, the pressure is approximately 1,100 times greater than at sea level. Equipment must be reliable, precise and accurate, and tested repeatedly before being used in real life situations. Having already acquired considerable experience with diving watches, Rolex was there with the Deep Sea Special, an experimental Sea-Dweller that survived the trip attached to the hull.

Fifty-two years later, in 2012, Canadian filmmaker James Cameron added a second chapter to the story of the Mariana Trench, descending to 10,908 meters in his DEEPSEA CHALLENGER submersible, taking pictures through his window that was 24.13 cm thick to withstand the pressure.  Another happy testament to the evolution of the first Rolex OYSTER from 1926, the experimental Rolex Deepsea Challenge timepiece, attached to the CHALLENGER’s robotic manipulator arm, worked perfectly.  Rated to 12,000 meters, it measured 51 mm in diameter with a thickness of 28.5 mm.

Other watch brands have contended for depth records.  The KALMAR 2 DEEP DIVER with resistance recorded at -25,000 meters; the CX Swiss Military Watch – a mechanical diving watch released in 2009 resistant to -6,000 meters; the oil-filled Bell & Ross Hydromax 11,100 meters production watch developed by Sinn; or the Sinn UC 12,000.  Additional diving watches from such celebrated brands as Panerai, or Blancpain celebrating in 2023 the 70th anniversary of its Fifty Fathoms, continue to assert their ranking among the best, if not in depth, for reliability and their proven histories.

But amid all this, Rolex was the record-breaking in real conditions reference known by everyone.

The surprise came in April-May 2019, when the experimental Omega Seamaster Planet Ocean Ultra Deep Professional broke the 1960 record held by Rolex, to reach a depth of 10,925 meters in the Mariana Trench.  One of the ‘Five Deeps Expedition’ led by explorer Victor Vescovo who reached the deepest depths of the five oceans on the DSV Limiting Factor submersible built by Triton, this descent was successfully accompanied by 3 of the watches, one attached to the robotic arm on the outside of the submersible.  Intended for professional use, this experimental watch that tested in lab pressure chambers to -15,000 meters measured 52.5 mm x 28.5 mm thick.  Too hefty for general diving purposes, Omega decided to make a more “wearable” Ultra Deep watch, inspired by the Seamaster Planet Ocean 600M.

And so it was that in March 2022, the Swatch Group presented the Omega Seamaster Planet Ocean Ultra Deep as part of its permanent catalogue collection.  Water resistant to 6,000 meters with its special case construction that requires no helium escape valve, the O-MEGASTEEL or titanium case measures 45.5 mm x 18.12 mm thick, equipped with in-house calibre 8912 for a power reserve of 60 hours. Priced from 12,200 Euros, COSC and METAS certified, it meets ISO 6425 standards for saturation dive watches.

Not to be outdone, on November 1st of 2022 Rolex introduced the ROLEX DEEPSEA CHALLENGE 126067, an adaptation of James Cameron’s experimental watch in 2012.  Due to its size of 51.4 mm x 28.5 mm thick, the watch and bracelet are made, for the first time by Rolex, in titanium - RLX brushed titanium - Grade 5, resulting in a 30% lighter weight than that worn by Cameron.  Rolex specifies that the resistance of each 126067, like all Rolex divers’ watches, is tested immersed in water within a special ultra-high pressure hyperbaric tank developed by Rolex and Comex (Compagnie Maritime d’Expertises).  Guaranteed waterproof to 11,000 meters, in a redesigned case construction with patented architecture, black Cerachrom bezel, Ringlock system, helium escapement valve and Oyster bracelet, the 126067 is powered by Calibre Rolex 3230, and can accompany divers in any environment – freedives, submersible dives or in hyperbaric chambers. With Superlative Chronometer certification, this watch is available to the public for 25,750 Euros, and completes the Rolex diving watch offer that lists many references, including the Oyster Perpetual Rolex Deepsea Sea-Dweller unveiled in 2008.  In 904L Oystersteel, waterproof to 3,900 meters, the Deepsea Sea-Dweller has a smaller diameter of 44 mm, and is equipped with Rolex Calibre 3235.  It is also Superlative Chronometer certified (COSC + Rolex certification after casing) and is priced from 14,050 Euros.

But 2022 was a year rich with surprises! One month later, on December 1st, independent French brand Ralf Tech introduced The Beast, capable of withstanding 4,000 meters in the lab and tested at   -3,000 meters in real conditions, making it one of the three “deepest’ serial watches of the year.  A relative newcomer to the general public, though not to enthusiasts of diving watches, Ralf Tech’s founder Frank Huyghe is himself a certified deep sea diver (scaphandrier) and instructor, choosing to trust his many years of personal experience and needs while underwater to design and wear his own watches for professional and recreational activities.

Establishing the company in 1996 to manufacture diving equipment for civilians and the military, his first watch, the Ralf Tech WR1 created in 2005 was a winner, as it was worn on the wrist of French scuba diver Pascal Bernabé on July 5th that same year, when he reached the as-of-yet unbeaten world record of -330 meters in a deep dive gathering off the shore of Corsica.  The win decided Huyghe to concentrate on watches, making what he knows best: sturdy, reliable, precise and accurate watches that are tested in real conditions.  In 2011 his WRX, for World Record eXtreme, was certified -1,000 meters, becoming the watch of the Combat Swimmers of the Commando Hubert of the French Navy (Marine Nationale).  In fact, Ralf Tech supplies special forces in and outside of France, alongside a growing demand from civilian divers.

Today, the brand has added The Beast to its other catalogue models that range in size from diameters of 39 to 47.7 mm, with certified depths that vary from -200 to -1,000 meters.  Tested over a 3-year period in hyperbaric chambers, on civil and military robots, on submarines that descend below 3,000 meters, and by Triton Submarines reaching -4,000 meters in static conditions, The Beast is presented in a 47.7 mm half cushion / round case, 17.7 mm thick including its 6 mm thick rounded sapphire crystal.  Designed for all divers, whether free divers, scuba divers, hyperbaric divers, or aboard submersibles, there is no need for a helium valve on this timepiece that seals the back of the watch to the case with an “encapsulation” system.  The Beast Manufacture First Edition, equipped with the RTM001, a 100% French manufacture (Pequignet) automatic movement with a power reserve of 77 hours, is priced at 6,800 Euros in 316L stainless steel, and 7,000 Euros in black PVD.  An electric version, The Beast Electric equipped with Swiss Micro Hybrid RTE001 created for Ralf Tech, has an autonomy of 100,000 hours, with retail prices of 2,800 Euros and 3,000 Euros respectively in steel or black PVD.

Of course, we don’t all need to be deep sea or saturation divers to wear one of these exceptional creations, but we do need to know that the tools to explore our oceans are there. Ah, if only Jules Verne were here today to experience them for himself, inspiring him to write about new adventures to be enjoyed by future generations. Imagine this: the ocean covers approximately 70% of the Earth’s surface, and while 24% of the global seafloor has been mapped thanks to high-resolution technology (source: NOAA Ocean Exploration), only 5% has actually been explored, and very little is known about the species that live there.  Estimated by scientists to number between 700,000 and 1 million, mostly animals and excluding most micro-organisms, roughly two-thirds are yet to be discovered or officially described.