The North Island is one of the two main islands of New Zealand, the other being the South Island. The island is 113,729 square km in area, making it the world's 14th-largest island.

Several important cities are in the North Island, notably New Zealand's largest city, Auckland, and Wellington, the capital, located at the southern extremity of the island. Around 76% of New Zealand's population lives in the North Island.

According to Māori mythology, that the North and South Islands of New Zealand came from the time of Māui, who was a demigod. Māui and his brothers were fishing from their canoe (the South Island) when he caught a great fish and pulled it from the sea. While he was not looking his brothers fought over the fish and chopped it up. This great fish became the North Island and thus the Māori name for the North Island is Te Ika-a-Māui (The Fish of Māui). The mountains and valleys are said to have been formed as a result of Māui's brothers' hacking at the fish.