If you buy from a link, we may earn a commission. Learn more A calendar is perhaps the most ubiquitous complication seen in watches, and also the most varied. From a simple date window to complex ...

Frederique Constant's incredibly affordable perpetual calendar, complete with a moon phase, now has a perfectly sized case ...

The watch’s calendar is not a normal Gregorian one, but rather an Islamic one, «requiring a custom modification of the calendar gears», wrote the luxury auction house. King Hassan II’s watch ...