Vacheron Constantin’s 270th anniversary gifts humanity the world’s most complicated wristwatch

In the rarefied world of high horology, where complications are measured not just in number but in technical and artistic prowess, Vacheron Constantin has proven itself time and again as the ultimate force to be reckoned with. That’s the culmination of a legacy of 270 years of uninterrupted production, ever since founder Jean-Marc Vacheron signed his first apprenticeship contract in 1755. “Do better if possible, and that is always possible” goes the house motto. 

Nothing since has changed that — not World Wars, not the 70s Quartz Crisis, and not the rise and fall of empires nor the inexorable march of industrialisation. And Vacheron Constantin continues to topple the dominoes of other watchmakers’ record-breaking attempts.

Its latest feat is the most complicated wristwatch ever crafted, hot on the heels of its most complicated pocket watch, the Les Cabinotiers The Berkley Grand Complication with 63 complications, released last year. Encased in the double-sided 45mm white gold case of the Les Cabinotiers Solaria Ultra Grand Complication – La Premiere, just 14.99mm thick, are a staggering 41 complications and 1,521 components — with 13 patent applications. 

Christian Selmoni, Vacheron Constantin’s style and heritage director, reflects on the achievement: “Because it is the most complicated wristwatch in the history of horology, the mechanism had to be arranged in the most logical and compact way possible. The main objective was to bring together all the main complications, timekeeping, astronomical, chronograph and chiming, on a single baseplate.”

This ingenious construction made it possible to create a wristwatch with harmonious proportions, he adds. “Many of the innovations of this watch are related to the solutions found to avoid adding bulk and to gain in energy efficiency.”

Unlike previous esteemed grand complications, which were developed by teams, the Solaria is the work of a single watchmaker over the past eight years. “He designed the movement, imagined the case — which is a direct response to the movement architecture — and guided the choice of finishes to be applied to every element,” Selmoni states of this singular accomplishment.

Three dimensions of time

The Solaria doesn’t just tell time — it interprets it through three distinct systems: civil, solar, and sidereal. And the new manufacture movement, Calibre 3655, is designed so that it can display all simultaneously, with a gear train specific to each of them.  

Civil time, governed by the 24-hour day, is displayed via central hour and minute hands, complemented by world time and GMT with day/night indications. Solar or tropical time, accounting for earth’s elliptical orbit, reveals the equation of time — the variance between true solar noon and standardised civil time — on a subdial at 6 o’clock.

Most intriguing is sidereal time, measured against the fixed stars rather than the sun, to be read on the reverse side of the watch. “It is rare for a timepiece to display civil time, solar time, and sidereal time coupled with the movement of the constellations,” notes Selmoni.

Celestial symphony 

The Solaria’s astronomical prowess extends further, weaving together five extraordinary complications in an unprecedented combination — with four related to the sun’s path on the watch front, and one on the back for the temporal tracking of celestial objects.

Located on the dial periphery is the sun’s position, indicated via a small yellow circle screen-printed on a rotating sapphire disc that also displays sunrise and sunset times, and the length of the day. 

On the 6 o’clock counter are the next three functions. The sun’s height above the horizon is expressed in degrees of angle that oscillate between 20° and 68°. The culmination of the sun, referring to the time when it reaches the highest point of its trajectory known as the solar noon, is also displayed. 

The indication for the sun’s declination corresponds with the angle formed between the earth’s equatorial plane and an imaginary line connecting the sun to earth. Varying according to the seasons in the northern hemisphere, it shifts between -/+ 23.5° in harmony with the solstices. In addition, this 6 o’clock counter displays the 13 astronomical constellations of the zodiac as well as the seasons, solstices, and equinoxes. 

Flip the watch around to marvel at the world-premiere, groundbreaking complication combining a split-seconds chronograph with a rotating representation of the celestial vault. Measured in hours, the elapsed time until the user will see the chosen star in the sky is indicated by a green triangle on the small counter in the dial centre. 

Surmounting complexity

The essential functions and astronomical complications aside, the watch also features a Gregorian perpetual calendar whose readings are supplemented by digital dating according to the ISO 8601 standard, and an astronomical moonphase that also displays the moon’s age plus spring and neap tides.

A hallmark of Vacheron Constantin’s expertise, the minute repeater mechanism employs the sophisticated Westminster carillon — with four hammers striking four gongs — to sound the hours, quarters, and minutes. 

Seven filed patents protect this area of innovation, including an optimised architecture, rectangular-sectioned gongs for amplified resonance, and gold-weighted steel hammers to minimise rebound. Selmoni highlights the challenge: “Redesigned with more compact dimensions and greater mass, the hammers and gongs are positioned on either side of the base plate to gain height and efficiency.”

Indeed, integrating 1,521 components into a wearable case demanded radical solutions. The movement is split into two connected sections: a base calibre handling timekeeping together with chronograph and striking functions, as well as an astronomical module just 2.8mm thick. 

A wear-resistant “plug-and-play” mounting system allows the two parts to be attached seamlessly to facilitate efficient energy transmission, which is one of the patent-pending innovations. Another is the design of a two-sided monobloc multi-cam wheel system for the solar-related functions, reducing the height of the mechanism while increasing precision. 

A masterclass in micro-engineering, manufacturing and assembly, the Solaria also showcases various sapphire discs as thin as 0.18mm, lightweight aluminium split-seconds chronograph hands, and ultra-thin sapphire crystals. On top of that, eight correctors, two push buttons, two selectors and an elegant slider for the minute repeater are successfully incorporated into the watch case.

Beauty in minutiae

Every component, no matter how tiny, is painstakingly thought-out and hand-wrought for maximum appeal and legibility. Remarkably, Vacheron Constantin has decided to steer away from traditional ornamentation so that the Solaria exudes a surprisingly, and emphatically, modern aesthetic. 

A restrained colour palette of white alternating with black, plus different shades of grey, are enhanced by plating, metallisation, and nine types of finishes. The minute repeater hammers are mirror-polished; the bridges are angled and polished as well as chamfered with a matt, satin-brushed, or brouillage finish; the jewel sinks are chamfered and the wheels circled; the main plate is circular-grained; and the barrel ratchet is sun-rayed. 

While kept to a minimum, bursts of exuberance lend the watch that extra something. The 5mm diameter earth dome in rhodium-plated gold is highlighted by the contrast between highly polished continents with sandblasted oceans. A yellow gold half-sphere renders the sun declination more magical. The two split-seconds chronograph hands, which traverse the star chart, are lacquered in green and red to maximise contrast, with the colours echoed in the 72-hour power reserve indication set on the movement periphery.

As awe-inspiring as the Solaria is, the creation is part of a long tradition of astronomical watches at Vacheron Constantin. It is safe to say it won’t be long before we are blown away by another.