The Citizen Promaster Aqualand, launched in 1985, is a quartz dive watch with a built-in depth gauge. A pressure sensor drives an analogue depth hand, so the diver reads the current depth on the dial without a separate instrument. It was the first dive watch to combine a depth sensor with an analogue display, and it came in a rugged resin or steel case with a rotating bezel. I could not find reliable official figures for the 1985 case size and depth range, so they are not stated here.

It sits in Citizen’s Promaster line of professional watches and followed the company’s earlier depth-meter experiments. The Aqualand idea was that a diver could carry a single instrument for both time and depth, and the model went through several generations.

Collectors treat the 1985 Aqualand as an early and unusual tool watch and one of Citizen’s technical landmarks, though it is niche and the sensor can be hard to service. The original is no longer made, but the Aqualand name remains in Citizen’s Promaster Marine range.