The Rolex Cosmograph Daytona was first introduced in 1963. Its earliest production reference was the 6239, a manually wound chronograph developed for timing racing-related events and named after Daytona Beach, Florida.
Rolex had already produced earlier chronographs, including the Reference 6234 and the transitional Reference 6238. The 6239 marked the important new Cosmograph design, with contrasting sub-dials and a tachymeter scale on the bezel for calculating average speed. Rolex’s association with Daytona’s racing culture helped give the watch its enduring name.
The timing of the name can cause confusion. The reference was introduced in 1963, but the word “Daytona” did not immediately appear on every dial. It was added below the “Rolex Cosmograph” signature in 1964 and later moved above the six-o’clock sub-dial. The first generation was also hand-wound; the self-winding Daytona arrived with the second generation in 1988.