The most complicated wristwatch

Made by

Vacheron Constantin, Geneva, in Les Cabinotiers, the department that makes commissioned watches and a yearly collection of one-off pieces. The Solaria is a single-piece edition, presented at Watches and Wonders Geneva in 2025, the year the maison marked 270 years of unbroken watchmaking.

What was new

41 complications in a watch worn on the wrist. Among them are a perpetual calendar, a tourbillon, world time, a split-seconds chronograph, a Westminster minute repeater and five astronomical functions. Four of these follow the Sun across the sky: its position in real time, its height, the time of its culmination and its angle of declination. The fifth, which the brand calls a world first, joins the split-seconds chronograph to a map of the sky, so that the wearer can time how long a constellation or a given star will take to stand at the centre of the field of view.

How it chimes

The minute repeater plays the Westminster carillon, the most elaborate of the chiming sequences, on four gongs struck by four hammers. Fitting it without making the movement thicker was one of the first problems, and 7 of the watch’s 13 patent applications concern the chiming mechanism alone.

Worth knowing

The Calibre 3655 has 1,521 components and took eight years of research and development. It sits in a white gold case 45 mm across and only 14.99 mm high. Its parts carry nine kinds of finish, from circling to satin polishing.

SourcesVacheron Constantin, Solaria Ultra Grand Complication – La Première · Vacheron Constantin, Les Cabinotiers · Watches and Wonders Geneva 2025, Vacheron Constantin · Time+Tide, introducing the Solaria