Count the small windows on this dial, one tucked just beside each of the twelve hour markers, and you have found the cleverest idea on the most complicated watch Rolex makes. Those twelve little apertures are the month display, and the way they work is quietly brilliant: the ring of windows corresponds to the twelve months of the year laid out around the dial like the hours, and at any given time exactly one of them is filled in red while the other eleven stay dark. The red window at the three o'clock position means it is March; when April comes the window at four lights up instead, and so on around the dial through the year. It is a way of showing the month that no other watch had ever used, reading the calendar off the hour markers themselves, and it is the signature of the Sky-Dweller, Rolex's travelling calendar watch.
That month display is the visible face of a mechanism Rolex calls Saros, and the name is telling, because the Saros is an astronomical cycle, the long rhythm that governs the recurrence of eclipses. Rolex borrowed it for the system that gives this watch an annual calendar, a mechanism clever enough to know that the months are not all the same length. A simple date watch has to be corrected by hand five times a year, at the end of every month shorter than thirty-one days. The Sky-Dweller's annual calendar carries those different lengths automatically, distinguishing the thirty- and thirty-one-day months on its own, so that the date clicks over correctly all year and needs adjusting only once, at the end of February. For someone who travels constantly and cannot be bothered resetting a watch every few weeks, that set-and-forget intelligence is exactly the point, and the twelve red-windowed months let them confirm at a glance where they are in the year.
The second half of the watch's purpose is written in the disc at its centre, because the Sky-Dweller is built for crossing time zones. Inside the ring of hour markers sits an off-centre twenty-four-hour display, a rotating disc read against a fixed triangle, that shows a second time zone independently of the main hands. A traveller can keep home time on the disc while the big central hands show the local time wherever they have landed, or the other way around, so that the watch always holds two places at once and the wearer never loses track of the hour back home. Annual calendar and dual time together make this a true globe-crosser's instrument, a watch that minds both the date and the two time zones that matter to a person living between cities.
All of which raises an obvious question: how on earth do you set a watch that does this much? And the answer is the third piece of cleverness, hidden in plain sight around the edge. The fluted bezel, which on any other Rolex is a fixed decorative ring, here actually rotates, and it is the control interface for the entire watch. Rolex calls it the Ring Command bezel. You turn it to one of its positions to choose what you want to adjust, the local time, the reference time, or the date, and then the crown sets that function; turn the bezel to a different position and the same crown now adjusts something else. It turns the bezel into a rotary selector switch, a mechanical menu, so that one crown can govern all the watch's functions clearly and without a cluttering of extra pushers. It is a genuinely original piece of interface design, and it means the most complicated Rolex is also, remarkably, one of the simplest to operate once you understand the bezel.
When the Sky-Dweller arrived in 2012 it was a significant moment for Rolex, the first entirely new watch concept and movement the company had introduced in a long while, a ground-up design built and patented in-house to prove the brand could still break new mechanical ground. It was Rolex stepping deliberately into higher complication, and doing it in the self-contained, robust, over-engineered way that defines everything the company makes, so that for all its sophistication the Sky-Dweller is built to the same standard of durability and everyday reliability as a simple Oyster.
This example wears the combination Rolex calls Rolesor, the marriage of steel and gold that the brand trademarked long ago and has made a signature, here pairing a stainless steel case and bracelet centre with yellow gold for the fluted Ring Command bezel, the winding crown, and the outer links. The two metals together give the watch a warmth and richness without committing to full gold, the bright steel cooled against the glow of the yellow gold. It rides on the Jubilee bracelet, the five-piece-link band first made for Rolex in 1945, supple and dressy and instantly recognisable, its fine links catching the light. The dial is a deep, legible black, a calm dark ground that sets off the applied luminous markers and hands, the red month window, and the printed scales with real clarity, and at three o'clock the date sits in its window beneath the Cyclops lens on the crystal. At forty-two millimetres the case has the presence to carry all this information comfortably, large enough to lay out the month windows, the twenty-four-hour disc, and the date without crowding, yet balanced and wearable.
That is what makes this Sky-Dweller so special. It is the most complicated watch Rolex builds, and it earns the title with real ingenuity: an annual calendar that shows the month in a ring of twelve small windows around the dial, a second time zone turning on an off-centre disc for the traveller, and a fluted bezel that secretly works as the control for the whole thing. Wrapped in the warm two-tone of steel and gold, strung on the classic Jubilee, and grounded by a clean black dial, it is a globe-crosser's watch that knows both the calendar and the clock of two places at once, and hides all that cleverness behind the unmistakable, unflappable face of a Rolex.
