In the midst of the Quartz Crisis, when all hope for the future of mechanical watches had been lost, Charles Vermot stored all the parts and drawings for the El Primero in the attic of the Zenith factory.
We are in the attic of the Zenith factory in Le Locle. Hundreds of watch parts, tools, molds, dials, and handwritten notes are arranged meticulously on wooden shelves… This attic, located near the section of the factory once connected to the railway, feels like a time tunnel into Zenith’s history. The drawings and components of the El Primero, the world’s first integrated automatic chronograph caliber, were kept here for many years. The story of El Primero — a chronograph ahead of its time — is as compelling as the watch itself.
Precision has always been in Zenith’s DNA. The brand’s founder, Georges Favre-Jacot, set out to create the most accurate wristwatch possible. In 1900, he was awarded the Grand Prize at the Paris Universal Exhibition. Between 1950 and 1954, Zenith’s caliber 135-0 won first place for five consecutive years in the Neuchâtel Observatory competition. In the first half of the 20th century, Zenith watches were renowned for their precision, chosen by observatories, banks, and even armies. The introduction of El Primero in 1969 marked the beginning of a revolutionary new chapter.
In 1965, as the brand approached its 100th anniversary, Zenith set out to create a caliber worthy of the milestone. Workshops in Les Ponts-de-Martel buzzed with activity. The new caliber was not ready in 1965, but after roughly seven years of development, the world’s first integrated automatic chronograph, El Primero, was finally born in 1969 — the same year the first tremors of the Quartz Crisis were being felt in the watch world. El Primero, meaning “first,” was officially announced on October 10, 1969.
The chronograph caliber was groundbreaking: operating at a frequency far above the traditional standard, El Primero ran at 36,000 VpH and could measure one-tenth of a second. With a power reserve exceeding 50 hours and an automatic winding system that kept the chronograph gears in place, it was a true innovation. At just 6.5 mm thick, it was also one of the slimmest mechanisms of its time. The first watches powered by El Primero were unveiled in September of that year. Their dials, with three subdials in contrasting colors, also introduced a new design language.
