February 9, 2023
Front of Audemars Piguet Millenary Quadriennium 18k rose gold watch

Audemars Piguet Millenary Quadriennium is one of the Audemars Piguet annual calendar.The watch  features the infamous AP escapement, so all-together a mighty interesting timepiece.

The Millenary has always been a bit of a an odd-shaped timepiece, often chosen by collector who’re perse drawn to a round case, and like the elegant oval shape, with beautiful alternating satin brushed and polished finishing, and stepped lugs. The Millenary always features an off centre dial, which was probably most notable on the magnificent Millenary Star Wheel that we reviewed extensively. The new Audemars Piguet Millenary Quadriennium has an off-centre dial for the hours, minutes, date, month and day of the week, and a small subsidiary dial for the running seconds. Front of Audemars Piguet Millenary Quadriennium 18k rose gold watch

As you can see on the photo above, the month is visible through a small aperture just above the Roman XII, and the day of the week is just below the Roman VI. From the centre of the dial come three hands: hours, minutes and the date. The perpetual calendar does not have to be adjusted at all. It automatically switches from February 28/29 to March 1st and automatically corrects for leap years.Side of Audemars Piguet Millenary Quadriennium 18k rose gold watch

The Millenary Quadriennium does not have to be adjusted at the end of February, at least 3 out of four years. This means it automatically takes into account that February has 28 days  and jumps to March 1st. Only in the leap year it has to be adjusted, because the calendar’s mechanism ‘thinks’ that February always has 28 days. It looks like the Audemars Piguet Millenary Quadriennium is the only watch which has to adjusted backwards in February.Audemars Piguet Millenary Quadriennium 18k rose gold watch caseback

The Roman numerals on the left-hand side are larger than those on the right-hand side, the font of the day of the weeks looks larger than that of the month, and two “bites” have been taken out of the dial, for the second sub dial and the balance wheel. The gold screws in the hour/minute dial and the sub second dial, are a reference to timepieces of yesteryear, however they also distract the attention, and so does the red pointer date hand. Maybe it’s just me, but I prefer the calmer design of the older Millenary like the Millenary Piano Forte. The balance wheel, which is held in place by a large bridge that is beautifully finished by hand, is part of the famous AP escapement. The double-hairspring compensates for potential poising flaws, and should improve the watch’ chronometry.