Rolex celebrates its toughest timekeeper turning 50

Originally released in 1971, the 39mm Explorer II 1655 is now a highly sought­after vintage piece for collectors around the world. It's loved for its 24-hour engraved bezel, baton hands, matte black dial and distinctive oversized orange arrow-point 24-hour hand. It was also a favourite among adrenaline junkies of the day - particularly a certain Hollywood icon with a passion for adventure and action. In fact, the 1655 is affectionately known as the Explorer II 'Steve McQueen'.

Fifty years on and the Explorer II has undergone some technical upgrades, while retaining many of the distinctive design elements employed by its predecessor. Its hefty and reassuring 42mm case and legible dial aesthetics remain, albeit with an optimised Chromalight display (also available with a black dial). And the in-house calibre 3285 movement (new for this model) deploys the best of Rolex watchmaking, with chronergy escapement, 70 hours of power reserve, blue Parachrom balance spring and Paraflex shock absorbers, making it more efficient and accurate.

Not satisfied with updating the Explorer II range in 2021, Rolex also released an all-new 36mm Oyster Perpetual Explorer. The sizing of this piece is significant because, at 36mm, it returns to the same dimensions as the original model, which was launched in 1953 following the first ascent to the summit of Mount Everest by Sir Edmund Hillary and Tenzing Norgay.

Available in a yellow Rolesor version (new combining Oystersteel and 18-carat yellow gold ), this Explorer model is a head-turning and luxurious take on the more understated Oystersteel 36mm with black dial. The approximate 70-hour power reserve delivered by both these models is courtesy of the new-generation calibre 3230 movement, which also boasts an optimised blue Parachrom hairspring (new manufactured in-house by Rolex in a paramagnetic alloy) that is 10 times more precise than a traditional hairspring in case of shocks.

Such reliability is crucial for scientists, conservationists and adventurers, who since the 1930s have been relying on Rolex watches as a functional and trusted tool when visiting some of the planet's most extreme and inhospitable environments. From the peaks of Everest and Annapurna to the depths of the Mariana Trench, having a wristwatch able to withstand the odd jolt, bump or impact is essential to an explorer's work.

For a range of watches so synonymous with human endeavour, many may have expected more daring updates to the range, but its exactly this kind of considered approach to change that is at the very heart of what makes Rolex so successful: the brand finds a winning formula, and only tweaks it when appropriate, rather than making drastic revisions. It certainly seems to keep the Rolex fans happy - be they intrepid explorers, or the kind of people who like to make Rolex predictions from the comfort of their sofa.

ROLEX EXPLORER II

Oystersteel 4 2mm case and bracelet, automatic movement, approximate 70-hour power reserve, fixed 24-hour graduated bezel, date window, waterproof to I00m.

ROLEX EXPLORER

Oystersteel and yellow-gold 36mm case and bracelet, automatic movement, approximate 70-hour power reserve, smooth yellow-gold bezel, black dial, waterproof to I00m.