Major Islands of the World

South Island

The South Island is the larger of the two major islands of New Zealand, the other being the more populous North Island. The Maori name for the South Island, Te Wai Pounamu, meaning "The Water/s of Greenstone" (greenstone being jade), possibly evolved from Te Wahi Pounamu which means "The Place Of Greenstone". The island is also known as Te Waka a Maui which means "Maui's Canoe".
In the 19th century, some maps named the South Island as Middle Island or New Munster, and the name South Island or New Leinster was used for today's Stewart Island/Rakiura.
The South Island has an area of 151,215 km² (58,093 square miles), making it the world's 12th-largest island. It has a population of 991,100 . Along its west coast runs the mountain chain of the Southern Alps with Aoraki/Mount Cook being the highest point, 3,754 m (12,316 ft) above sea level.
The South Island is often called the Mainland (somewhat humorously) because it existed first according to Maori legend, and is larger than the North Island. About a quarter of New Zealand's four million inhabitants live in the South Island.

Regions
There are seven local government regions covering the South Island and all its adjacent islands and territorial waters. Four are governed by an elected regional council, while three are governed by territorial authorities (the second tier of local government) which also perform the functions of a regional council and thus are known as unitary authorities. There is one exception to this, Nelson City is governed by an individual Territorial authority to its region (Tasman Region). The Chatham Islands Council is often counted by many as a unitary authority, but it is officially recognised as a part of the region of Canterbury.