The Rolex Deepsea Challenge enjoys a double heritage:

• In historical terms, it is the heir of the 1960 experimental Oyster Deep Sea Special, which dived to the bottom of the Mariana Trench with the bathyscaphe Trieste to a depth of 10,916 metres (35,814 feet).

The Mariana Trench, which stretches in an arc around the Mariana Islands in the Pacific Ocean, is the deepest part of the world’s oceans. The deepest point in the trench, known as Challenger Deep, lies some 11,000 metres (nearly 7 miles) below the surface. If Mount Everest, the world’s tallest peak, were set in the trench, there would still be approximately 2,000 metres (1.3 miles) of water above it. The trench was created by subduction, the sideways and downward movement of the edge of the Pacific tectonic plate into the mantle beneath the Mariana Plate.

Challenger Deep was named after the 1875 British Royal Navy Ship HMS Challenger, the first vessel to sound the depths of the trench.

In January 1960, Swiss oceanographer Jacques Piccard and the then Lieutenant Don Walsh manned the 150-tonne, U.S. Navy bathyscaphe Trieste for the journey to Challenger Deep and back. Since then, only unmanned vessels have descended to such depths.

1960 – Trieste	2012 – Deepsea challenger
The bathyscaphe 18.1 m (59.5 ft) long, oriented horizontally Weight: 150 tonnes Buoyancy provided by gasoline tanks No technology to collect samples or specimens No external technology to take photographs	The submersible 8 m (26 ft.) tall, “vertical torpedo” shape Weight: 12 tonnes Buoyancy provided by Isofloat syntactic foam Equipped with multiple HD cameras, including some that are 3-D capable for film production
The dive Naval expedition Two-person Depth reached; 10,916 m (35,814 ft) Dive time: nine hours including just 20 minutes at the bottom Discovery of deep-sea life forms	The dive Scientific expedition One-person Depth target: about 11,000 m (36,100 ft) Estimated dive time: about 10 hours including six hours at the bottom Collection of samples; filming and photography
The watch Rolex Deep Sea Special experimental watch Waterproof to 10,916 m (35,814 ft) Attached to the exterior of the bathyscaphe Diameter: 42.7 mm Thickness: 36 mm	The watch Rolex Deepsea Challenge experimental watch Waterproof to 12,000 m (39,370 ft) Attached to the submersible’s manipulator arm Diameter: 51.4 mm Thickness: 28.5 mm

Fifty-two years ago Rolex made watchmaking history when it joined the bathyscaphe Trieste, crewed by Swiss oceanographer Jacques Piccard and the then U.S. Navy Lieutenant Don Walsh, as the Swiss-designed bathyscaphe descended to what was at the time the deepest-known point in the ocean.

An experimental Rolex Deep Sea Special wristwatch was attached to the exterior of the Trieste when it touched the bottom of the Mariana Trench in the Pacific Ocean on 23 January 1960, reaching a depth of 10,916 metres (35,814 feet). It successfully withstood tremendous pressure that no submersible, let alone watch, had confronted before and that no human could ever survive. The dive marked the culmination of a long association with Jacques Piccard and his father Auguste Piccard, the inventor of the bathyscaphe, as they stretched the boundaries of deep-sea exploration. It was also the fruit of decades of unrelenting development of the waterproof wristwatch, which was invented by Rolex.

Rolex has always been associated with exploration of the planet’s most extreme frontiers and pushing the limits of human endeavour, in keeping with the spirit instilled by its founder, Hans Wilsdorf. He actively led the company through the most adventurous decades of the 20^th century, a period marked by discovery of the world about us and immense technological progress.

The Swiss watchmaker has, in particular, nurtured a special relationship with the sea and its deepest reaches from the very beginning. Rolex is simply the natural partner for Deepsea Challenge, a scientific expedition that heralds the beginning of a new era in marine exploration.

Robust, precise and highly reliable Rolex Oyster watches have not only accompanied the Trieste on the world’s deepest dive. They also equipped the expedition by Sir John Hunt, Sir Edmund Hillary and Tenzing Norgay to the top of the world in 1953 – leading to the pioneering ascent of Mount Everest – and Chuck Yeager when he broke the sound barrier in 1947.

The Piccards, Don Walsh and their bathyscaphe followed in the steps of those adventurers, providing the ultimate test for Rolex technology and the experimental Deep Sea Special watch. After the Trieste surfaced from its record dive in 1960, a cable was sent to Rolex headquarters: “Happy announce to yo your watch as precise at 11,000 metros as on surface. Best regards, Jacques Piccard”.

Exploits of the kind have also provided a proving ground for Oyster wristwatches from the very beginning. Rolex is in its element in water, and the name chosen for its iconic collection of waterproof wristwatches is no accident. Waterproofness was a fundamental feature that helped to make the wristwatch reliable and accurate. Rolex invented the first waterproof wristwatch in 1926, and provided a real-life demonstration of its waterproofness when Mercedes Gleitze swam the English Channel wearing one a year later. The Oyster watch innovated with its screw-down case back, bezel and winding crown, forming the essence of the modern-day sealed case that protects a high-precision movement. Such reliable waterproofness is today inherent in every Rolex Oyster Perpetual model.

Rolex has also sustained and extended its position at the forefront of watchmaking for diving and underwater research with ground-breaking innovations.

During the 1940s and 1950s, developments in diving technology paved the way for a boom in underwater exploration. The exacting professional diving community came to treasure Rolex watches as essential tools of the trade and even helped in their development.

• The iconic Oyster Perpetual Submariner, first unveiled in 1953, is today waterproof to a depth of 300 metres (1,000 feet).
  
• The Sea-Dweller model, first presented in 1967 extended the depth limit for Rolex waterproof watches to 610 metres (2,000 feet) then 1,220 metres (4,000 feet) in 1978.
  
• And ultimately the Rolex Deepsea, introduced in 2008, illustrates the supremacy of Rolex in mastering waterproofness. This new-generation divers’ Rolex is waterproof to a depth of 3,900 metres (12,800 feet), providing a substantial safety margin for those working in the open water at great depth. Each Rolex Deepsea is individually tested in a specially built hyperbaric tank in Geneva.

The test tank for the Rolex Deepsea was developed with specialist engineers from COMEX (Compagnie Maritime d’Expertises), a world-renowned French company specializing in underwater engineering and hyperbaric technologies. Rolex has been collaborating with COMEX for decades and supplied watches to equip its elite divers.

Timepieces such as the Rolex Deepsea and the state-of-the-art, experimental Rolex Deepsea Challenge carried by James Cameron’s submersible are the product of nearly a century of finely tuned know-how and innovation. They attest to the pursuit of perfection and the finest engineering. Nonetheless, Rolex’s affinity with the deep does not stop there. It extends to active and sustained sponsorship of renowned marine researchers and ocean exploration, supporting excellence in the advancement of human knowledge.

Don Walsh remains part of the Rolex family, while Rolex Testimonees include renowned oceanographer and explorer Sylvia Earle as well as underwater photographer and marine naturalist David Doubilet. Rolex was associated with The Deep, an exceptional exhibition of deep-sea creatures conceived by film-maker Claire Nouvian in collaboration with scientific researchers, providing visitors with a unique opportunity to discover some of the mysteries of the Earth’s largest reservoir of life. Rolex supports the Our World – Underwater Scholarship Society, funding young Rolex Scholars to gain hands-on experience with leaders in marine-related research including on scientific expeditions. And the adventurous new spirit of marine exploration actively embodied by Deepsea Challenge is also present in SeaOrbiter, a project for a new-generation vessel to monitor ocean life and enhance global scientific research, also supported by Rolex.

In the same vein, James Cameron’s Deepsea Challenge is taking us on a new journey, revealing the secrets held by the ocean floor for centuries and shedding light on the deepest frontier accessible to mankind.