A Stunning Pioneer: Patek Philippe Ref. 1518 Perpetual Calendar Chronograph

In 1941 the world was in the midst of WWII, yet this was also the time that Patek Philippe introduced a landmark watch, the ref.1518. This was not only Patek Philippe's very first watch that united both a perpetual calendar with a chronograph, but also the very first time that such a watch was made in series.