Ardath Watch Company was a Swiss watch manufacturer active for most of the 20th century.

Ardath was founded in 1935 in Geneva by Edmond Dreyfuss, a veteran of the watch industry. The company specialized in mass-market Roskopf watches, before moving into upscale Swiss lever watches in the 1950s. After Dreyfuss' death in 1954, the company followed industry trends, introducing waterproof watches and a small “5 silver coin” model just 17.2 mm diameter.

In 1962, Ardath introduced the Long Distance, a pioneering dual timezone watch with two separate movements side by side in a single oversized dial, one automatic with date and the other hand-winding. This was also sold in Islamic countries as the “Wisdom” model, which showed prayer time in Mecca. In 1968, the Super Long Distance model featured two automatic movements in a long rectangular case. 1973 saw the introduction of the Hostess Long Distance, a ladies version with two separate cases, one with a black and another with a white dial.

Another novelty in the 1960s was a line of watches with interchangeable components The Convertible pendant watch attached to different case backs, the Pluricases was similar in a wrist form, while the Versatile (for women) and Tyematcher (for men) had interchangeable dials. In 1967, Ardath introduced the Reef Diver, part of their “helmet line” of supercompressors, and this would become a sub-brand with many models.

Ardath remained on-trend throughout the 1970s, with integrated bracelets and porthole bezels. The Geneva line presaged the gold case/black dial look of the 1980s and had the look of a museum watch, with gold or jewel pips at 12 and 6. The company was late to introduce quartz watches, lacking a movement of their own, but pivoted in that direction fully after 1977.

Through the 1960s, Ardath sold watches under the names of Ardent, Ardaco, Alverna, Long-Distance, Denis-Diver, Reefguard, Remember-Dazzling-Star, and Razor-Edge. They would return to the name in 1979, launching a line of ladies models under the “Montres Ardath et Paul Ardent” brand. These would pick up where the Geneva line left off, even using the same “Style of Geneva” tag line. Many would carry the Ardath name, but the company also branded these with just “Paul Ardent.” This brand did not last much into the 1980s, though.

In 1985, Ardath celebrated their 50th anniversary with the Pythagore model, an avant-garde dress watch with black “skeleton” bracelet and diamond-shaped case.

The Alverna brand continued into the 1980s, with the River model launched in 1986. A skeleton mechanical version with gold bracelet similar to the Pythagore appeared the following year, followed by the novel Halo model.

Ardath's final appearance at the Basel Fair came in 1993, after which the brand became defunct. The final product shown was simply a re-edition of the Super Long Distance dual-movement watch.

• Two Movements, One Case: Ardath Long Distance