In the early 1930s, nearly 50 years after Greenwich, England was established as the prime meridian of the world’s 24 main time zones, Swiss watchmaker Louis Cottier created a mechanism to display them all on a single watch dial. By the end of the decade Vacheron Constantin had produced the first worldtimer pocket watch, and Patek Philippe is credited with creating the first Cottier-inspired World Time wristwatch. (Time has also been good to their value: In 2002 a 1939 platinum Patek Philippe World Time watch set a then record at auction, selling for more than $4 million.) By the 1950s Rolex tried to further simplify the complication by creating a watch, the GMT-Master, set to Greenwich Mean Time and a home location, a function especially useful for pilots.

Today, of course, worldtimer watches are invaluable to every corporate Magellan who does business across multiple time zones. Patek still makes a World Time watch that looks remarkably similar to its early models, while Greubel Forsey has elevated the GMT with a rotating globe on the dial and a world time disc with 24 cities on the back of the movement. And every time you look at your wrist, you are reminded just how small a world it is after all.