And for those who follow the global markets, Girard-Perregaux's watch provides a financial function that keeps track of opening and closing times on the stock exchange in New York, London, Hong Kong and Tokyo.

WSJ: World-Time Keeping Wristwatches

He says, while the M1 has changed somewhat since the opening of that first stretch 50 years ago, it still performs its function very well today.

BBC: The M1 celebrates its 50th birthday