Rolex has an unparalleled reputation for producing some of the world’s highest quality purpose-built watches, and the Sea Dweller is no exception whatsoever. Upon first glance, the uninitiated would be forgiven for mistaking one of these watches as a mere Submariner, but upon closer inspection it reveals itself to be anything but. While they share a design language with date-equipped Submariner models, the Sea Dweller is a decidedly more capable dive watch, with a history as impressive as its the depths it can comfortably descend to. Without further ado, let’s go deep into this family of timepieces’ history, and what makes them so very special.

The globally revered watchmaker’s days of dive watch production date back to the early 1950s with the release of the Submariner. After the introduction of this now iconic watch, it would later become evident that the envelope needed further pushing, largely as a result of the Sub’s shortcomings in especially daring situations. Saturation divers — including those who participated in the United States Navy’s SEALAB expeditions of the 1960s — were left yearning for more after the crystals of their Submariners popped out of their cases during post-dive decompression. After expressing this concern to Rolex, research and development began to solve this considerably niche issue, experienced exclusively by the most hardcore of divers.

Following a bout of intense diagnostics, the problem was determined to be a buildup of helium within the watch case, as a result of helium’s presence in the breathing gas mixture used by saturation divers below the surface. Without a designated point of egress, the helium would force the crystal out of the case, making it clear that a more elegant solution to the gas’ escape was needed. Rolex acted accordingly through the development of the Swiss patent CH499246 – a custom mechanism allowing for the freeing of helium particles in a controlled manner. During the process of testing the newfangled escape valve, watches fitted with it were dubbed “Sea Dwellers,” and subjected to extended stays at great depths, ensuring reliable performance beyond the needs of even the most adventurous.

Both the filing of the revolutionary patent and aforementioned trials gave life to the Sea Dweller in 1967, in the form of the Ref. 1665. To accommodate the escape valve-afforded depth rating of 2000ft, or 610m, the new diver featured a thicker case, characterized by a protruding caseback to secure its movement. Additionally, this watch was distinguished from its less capable cousin thanks to the valve opening at the nine o’clock position on its case’s side, marking a new and exciting chapter in the Rolex dive watch story. All of this was accomplished while maintaining the 40 mm form factory of the celebrated Submariner, ensuring that both watches would enjoy iconic appeal.

Like other Rolex sports models, the Sea Dweller was produced in a number of variants over the years, making it wholly possible to build an important collection focused around the single model. The relatively recent Ref. 16600 represents the perfect way to dip your toe in the waters of Sea Dweller collecting, featuring more modern facets like the advanced Cal. 3135 movement and a solid end link bracelet, but after wetting your feet, you’ll surely want to dive deeper into the realm of vintage references. Most begin the next step of this journey with a Ref. 1655 “Great White,” featuring white Sea Dweller text and the same depth rating that first made the watch famous, but the one to have will always be a “Double Red.” As the name would suggest, these early variants produced from 1966-1977 feature two lines of text in red, along with the words “Submariner 2000,” indicating the diver’s origins in the Submariner model. Regardless where your Sea Dweller collection starts or ends, there’s no wrong answer, as each and every execution of the next level dive watch is nothing short of over-engineered perfection.