Rolex Deep Sea Special at the deepest point on the planet

The Rolex Deep Sea Special was a specially developed experimental watch designed to demonstrate that a mechanical watch could withstand the enormous pressure of the deep sea.

On January 23, 1960, Swiss oceanographer Jacques Piccard and US Navy officer Don Walsh attached a Deep Sea Special to the exterior of the Trieste, their manned bathyscaphe. The Trieste reached a depth of approximately 10.9 kilometers in the Challenger Deep of the Mariana Trench – the deepest known point on Earth. There, the pressure is approximately 1,100 bar, more than a thousand times that at the surface.

The watch remained functional. Its most striking feature was the highly domed, thick crystal, which was designed to better withstand water pressure. The case was also particularly robust and was further reinforced throughout the development series. The Deep Sea Special was not a regular retail model, but a technical demonstration piece. Rolex had previously tested various prototypes; the watch attached to the submersible was part of this experimental series.

An important distinction: The Deep Sea Special was mounted on the exterior of the submersible, not on a diver's wrist. Later watches such as the Rolex Deepsea and Deepsea Challenge adopted the idea of extreme pressure resistance, but are independent models.

The expedition was both a spectacular field test for the watch and a milestone in deep-sea exploration: Piccard and Walsh were the first humans to reach the Challenger Deep.