Auckland lies on the North Island of New Zealand, of which it is the largest city by population with 1,300 million inhabitants. The city sits on the volcanic field of the same name, on the isthmus that links the Northland peninsula to the rest of the island between the Tamaki River and Mangere Inlet, along with the natural harbours of Waitemata to the north and Manukau to the south. The Auckland region enjoys a particularly mild oceanic climate, with warm, humid summers and mild but fairly rainy winters. It is also one of the sunniest regions of New Zealand.