Milford Sound is a fjord in the south west of New Zealand's South Island, within Fiordland National Park, Piopiotahi (Milford Sound) Marine Reserve, and the Te Wahipounamu World Heritage site. It has been judged the world's top travel destination in an international survey and is acclaimed as New Zealand's most famous tourist destination. Rudyard Kipling had previously called it the eighth Wonder of the World.
Milford Sound is named after Milford Haven in Wales, while the Cleddau River which flows into the sound is also named for its Welsh namesake. The Maori named the sound Piopiotahi after the thrush-like piopio bird, now extinct. Piopiotahi means "a single piopio", harking back to the legend of Maui trying to win immortality for mankind - when Maui died in the attempt, a piopio was said to have flown here in mourning.
Lush rain forests cling precariously to these cliffs, while seals, penguins, and dolphins frequent the waters and whales can be seen sometimes. The sound has been identified as an Important Bird Area by BirdLife International because it is a breeding site for Fiordland Penguins.
The beauty of this landscape draws thousands of visitors each day, with between 550,000 and 1 million visitors in total per year. This makes the sound one of New Zealand's most-visited tourist spots, and also the most famous New Zealand tourist destination, even with its remote location and the long journey from the nearest population centres.
Almost all tourists going to the sound also take one of the boat tours which usually last one to two hours. They are offered by several companies, departing from the Milford Sound Visitors' Centre. There is also the option of extended overnight cruises on Milford Sound.
Tramping, canoeing, and some other water sports are possible. A small number of companies also provide overnight boat trips. There is otherwise only limited accommodation at the sound, and only a very small percentage of tourists stay more than the day. Many tourists visiting Milford Sound usually stay in Te Anau to the south or Queenstown to the east.
An underwater tourist observatory found in one of the bays of the sound provides viewing of black coral, usually only found in much deeper waters. A dark surface layer of fresh water, stained by tannins from the surrounding forest, allows the corals to grow close to the surface here.