Breguet’s quarter-millennial celebrations continue with the Marine Hora Mundi 5555, a reprise of the unique piece created for Only Watch two years ago. The world time wristwatch now returns with a phosphorescent enamel dial – that is notably grand feu on sapphire crystal – and a case in “Breguet Gold”. While the attire is new, the Hora Mundi 5555 still retains the clever movement that has a world time function that is instantaneously switchable between two pre-set time zones and unique amongst travel watches.

Initial Thoughts

Breguet facelifted the aging Marine line starting about eight years ago, but the integrated bracelet design language still feels fresh, though arguably remains unproven compared to long-established peers in the luxury sports watch segment. The Marine Équation Marchante 5887, which introduced the new look, leaned heavily on its excellent movement – it’s perhaps the best equation of time complication yet made – as a crutch supporting an experimental design. More practical and simpler models followed; the Marine Hora Mundi is certainly practical but not simple.

The Marine Hora Mundi 5555 is likewise powered by an impressive movement, and one incorporating a complication apt for a sports watch, but the watch also has a metiers d’art distinction with its enamel dial. That is unusual for a sports watch, but the Marine is an unusual sports watch. The enamelling itself is even more unusual, done on sapphire using phosphorescent pigments, and very well executed.

Even better, Breguet offers owners the opportunity to customise the 24 cities marking the time zones, which should be the case with every world time at this price. Unfortunately, it doesn’t overcome the limitations of its genre, and daylight savings means the time will be wrong for cities in the western world half the time, and incompatible with most of south Asia.

A Time Traveller

Despite the name translating from Latin as “world time”, the Marine Hora Mundi 5555 is not actually a world time, but more. The name is a holdover from 1997 when Breguet added a traditional world time, the Hora Mundi 3700, to its fledgling Marine collection.

The three position crown winds the watch and sets both the time and date. The second crown at eight 0’clock adjusts the time zone, with the hands, day/night indicator, and date changing in real time as you cycle through cities in the window at six. That is useful but not unusual, however, the genius of the Hora Mundi lies in its time zone switching function: pressing that same button instantly switches to another, pre-set time zone.

When switching between time zones, the cities ring, sun and moon disk, hour hand, and date all change in an instant. This is accomplished with a hammer and heart-cam system, similar to a chronograph’s reset mechanism.  Unlike most dual-time watches with “home” and “local” times, neither time zone is privileged since the switching is instantaneous and displays the information identically. But, like most in its genre, the Hora Mundi struggles with daylight savings time, and half-hour time zones.

In-Depth Dial

Like the regular production Hora Mundi 5557 that does without the enamelled dial, this 250th anniversary edition uses a pair of superimposed dials. The lower dial is 18k gold with engine turned lines of latitude and longitude and a blue finish. On top is an enamelled sapphire disc with extra long dial feet, which pass through holes in the lower dial layer to mount directly on the movement.

On the Hora Mundi 5555, tampon printing transfers the continental contours in transparent enamel to one side of the sapphire disc, which are then painted upon by hand to add depth. Clouds are added on the reverse side, and finished off with dots of luminous enamel to mark the cities.

Breguet compounded phosphorescent additives into the glass enamel powder to make the cities glow in the dark, which is reminiscent of the aventurine enamel used on the Tourbillon Sidereal 7255, another of its 250th anniversary editions. The day/night indication is also noteworthy, made of Breguet gold that’s hand-hammered and rhodium-plated on one half to represent the moon.

The  case work is to Breguet’s usual standard – very good – and is water resistant to 100 m with a screw-down crown. The second crown that adjust the world time function doesn’t screw down, and is more akin to a water-resistant chronograph button.

The new Hora Mundi 5555 is currently not offered on a bracelet. The regular production 5557 is, however, but its bracelet is in rose gold, not Breguet gold, so it may fit but will not match the case.

The calibre underneath stems from cal. 777Q, one of Breguet’s first proprietary movements, and not one based on historic F. Piguet, Lemnia, or Longines designs.

More importantly, this calibre introduced silicon parts to Breguet in 2006. It is finished to industrial fine watchmaking standards, with a nautically themed Breguet gold rotor. Interestingly Breguet has recently adopted machined groove separating the Cotes de Geneve on the bridges, similar to Rolex’s approach, but here meant to evoke the wood decking of sailboats.

Key facts and price

Breguet Marine Hora Mundi 5555
Ref. 5555BH/YS/9WV

Diameter: 43.9 mm
Height: 13.8 mm
Material: 18k Breguet gold
Crystal: Sapphire
Water resistance: 100 m

Movement: Cal. 77F1
Functions: Hour, minutes, central seconds, dual pre-set time zones with an instant jump and synchronised date, day/night indicator and city display
Winding: Automatic
Frequency: 28,800 beats per hours (4 Hz)
Power reserve: 55 hours

Strap: Leather strap with folding clasp

Limited edition: 50 numbered examples
Availability: Though Breguet boutiques
Price: US$104,700

For more information, visit Breguet.com.

Now in its 28th year, the Cartier Prize for Watchmaking Talents of Tomorrow is open for candidates. This year’s theme is “Shifting the Balance: Reading and Perceiving Time Differently” and encourages applicants to propose novel or unusual time displays, inspired by the recently revived Tank à Guichets.

The prize is open to third and fourth year apprentice watchmakers and techniciens ES en Microtechniques in Switzerland, or young people in any equivalently rigorous program in France, Germany, Belgium, or employed at Cartier (which unsurprisingly is one of the largest employees in the Vallee de Joux). The brand will also consider applicants outside this scope on a case-by-case basis.

Cartier accepts applications in French, English, and German, which must include an introduction video, project pitch, and sketch of the creation. This portal closes on October 31 2025. A five member jury, which includes Kari Voutilainen, will select six technicians and six apprentices, to be announced in December.

The 12 chosen candidates will pair up with a mentor and have only 80 hours over three months to construct their respective vision using a Cartier cal. 012 alarm clock movement and a budget of CHF500. The application includes normally proprietary technical documentation on this movement to help the prospects plan their projects.

Candidates will document the build in a digital logbook, recording and explaining each step, and keeping track of the 80 hour time budget. The reconvened jury will examine both the finished timepiece and logbook, selecting three winners from the apprentices and three from the technician.

All winners receive a Cartier watch, and the first place winners will “be offered opportunities to immerse themselves in the Cartier Watch Manufactures and Ateliers”, which sounds very much like a job offer.

Read more on PrixCartierTalentsHorlogersDeDemain.com.