Fiordland is a geographic region of New Zealand that is situated on the south-western corner of the South Island, comprising the western-most third of Southland. Most of Fiordland is dominated by the steep sides of the snow-capped Southern Alps, deep lakes and its ocean-flooded, steep western valleys. Indeed, the name "Fiordland" comes from a variant spelling of the Scandinavian word for this type of steep valley, "fjord".

Fiordland features a number of fiords (often named sounds), of which Milford Sound is the most famous, though Doubtful Sound is even larger and has more, and longer, branches (but is also less accessible). Situated within Fiordland are Browne Falls and Sutherland Falls, which rank among the tallest waterfalls in the world and New Zealand's three deepest lakes, Lake Hauroko, Lake Manapouri, and Lake Te Anau. This part of New Zealand has a very wet climate, receiving 6,300mm of rainfall per year.^{[citation needed]}