Underwater Observatory

The beauty of Fiordland continues below the sea. Milford Sound contains unique and beautiful marine life, and the Underwater Observatory is the perfect way to get up close and observe it.

Overlaying the sea water in the fiord is a layer of fresh water, the result of high annual rainfall in Fiordland. This combined with the narrow shape of the fiord causes a phenomenon known as deep water emergence where light is not allowed to penetrate past the fresh water. This creates a similar environment to the deep ocean at a much shallower depth, allowing visitors the chance to see deep sea species close up.

The Milford Deep Underwater Observatory is nestled in Harrison Cove, beneath Pembroke Glacier, amongst the towering mountains of Fiordland National Park. Visitors disembark at the terminal and descend 10.4 metres (34 ft) into the large, fully air conditioned underwater viewing chamber. From within a metre, observe the intimate and undisturbed life of a vibrant underwater community. Watch the ever-changing underwater environment as corals, anemones, sponges and fish species carry on unaffected within their own natural habitat.

Unlike an aquarium, the fish are free to come and go; it is the people who are contained. This provides a unique opportunity to observe real life situations deep below the surface of the fiord, quite different from the artificial environment of an aquarium. Include a visit to the Milford Deep Underwater Observatory with a scenic cruise on the Sound, or if on limited time, take a short cruise simply to visit the observatory.