First presented in 2022, the Tourbillon 24 Secondes Architecture introduced a radically open approach to movement construction, where architecture itself became the dial. Composed of 354 components, the movement is fully exposed, turning structure into visual identity. From the outset, Greubel Forsey announced that this calibre would be produced for only five years and limited to 66 timepieces. Having built and delivered 55, the Atelier now concludes this chapter with a final edition of 11 timepieces. This last interpretation adds a subtle increase in contrast while preserving the original purist philosophy: the design of the timepiece is the movement itself, fully displayed and visible from all angles.
When the Tourbillon 24 Secondes Architecture was unveiled in 2022, it marked a clear departure from traditional movement construction. Rather than placing a movement inside a case, the entire project was conceived as an architectural composition – a mechanical landscape suspended in space, where each component contributes equally to function and visual structure.
Its convex, conical-frustum case construction was developed to support this idea. Measuring 47.05 mm across the caseband and 45.50mm at the bezel, the titanium case integrates sapphire crystal around the full periphery, allowing the movement to remain visible not only from the dial side but also from above, below and every lateral angle. Light becomes an active element of the composition, revealing depth, shadows and surfaces throughout the movement. Around the dial opening, the engraved words Architecture, Harmonie, Innovation, Technique, Bienfacture, Passion, Science, Exclusivité express the conditions under which this timepiece was allowed to exist – the standard against which every component was measured.
At the heart of the calibre lies the inclined 24-second tourbillon, positioned at 6 o’clock and rotating once every 24 seconds at a 25° inclination. Combined with a fast rotation speed, this architecture contributes to chronometric stability while reinforcing the dynamic visual character of the timepiece. The movement comprises 354 components, including an 86-part tourbillon cage weighing only 0.38 grams, powered by three fast-rotating coaxial barrels delivering a 90-hour chronometric power reserve.
The Architecture concept was conceived around openness and purity. Polished spherical titanium bridges emerge from a frosted titanium mainplate, while the central elements appear suspended, almost detached from the movement base. Hours and minutes are indicated by large openworked hands mounted on a tripod bridge, accompanied by a small seconds display and a sector power-reserve indication. Every element is arranged to maintain visual balance while exposing the mechanics as completely as possible.
This final edition introduces a discreet evolution. The contrasts between surfaces are slightly reinforced, enhancing legibility and depth without altering the original intent. The aesthetic remains deliberately restrained: the movement is not decorated by design – it is the design. Architecture, mechanics and finishing remain inseparable, preserving the purity that defined the first edition.
Observers who looked closely may have noticed an inscription on the caseback: “Architecture 1.” Discreetly engraved, it served as a quiet indication that this architectural approach could one day be explored again in a different form.
This Tourbillon 24 Secondes Architecture therefore represents both an ending and a statement. It remains faithful to the original vision introduced in 2022 – a timepiece where the movement is fully exposed, fully legible and fully responsible for its own aesthetic identity – while offering a final, more contrasted expression before the calibre is permanently retired
