Prevailing westerly winds blow moist air from the Tasman Sea onshore here into the mountains; the cooling of this air as it rises produces a prodigious amount of rainfall, exceeding seven metres in many parts of the park. This supports the lush temperate rain forests of the Fiordland temperate forests ecoregion.
During the cooler past, glaciers carved many deep fiords into this mountainous region, the most famous (and most visited) of which is Milford Sound. Other notable fiords along the coast include Doubtful Sound and Dusky Sound.
Fiordland's coast is steep and crenellated, with the fiords running into valleys of the southern ranges of the Southern Alps, such as the Kepler and Murchison Mountains. At the northern end of the park, several peaks rise to above 2000 metres.
Road access to Fiordland is restricted to one highway that runs east to Te Anau and from there turns north, skirting the edge of the park before entering it close to the headwaters of the Eglinton River. From there it crosses the nortwest corner of the park, reaching its terminus at Milford Sound. South of Te Anau a smaller road links to Manapouri. A minor road also links Doubtful Sound with the western edge of Lake Manapouri.
Light aircraft and helicopter services link with Milford Sound, which also has a small boat marina.
Helicopter hunting
As long ago as the 1920s, the park was plagued with introduced European deer, detrimental to the native New Zealand flora and fauna. The government placed a bounty on the deer, paying local hunters for each animal removed from the park. Combined with the market for venison and deerskin, by the 1960s this had proved a lucrative enough business for several hunters to invest in helicopters, the better to travel through this rugged landscape. Deer populations plummeted as a result, and competition among hunters grew more fierce. Arguments between men in helicopters with high-powered rifles resulted in more than one pitched battle mid-air over the park. The government soon stepped in to prevent such extremes; combined with a growing farm-raised deer industry, helicopter hunting has declined steeply in more recent years. However, its legacy lives on, as dozens upon dozens of former hunting helicopters these days carry tourists on sight-seeing aerial journeys.
