Some rock formations of volcanic origin are among the oldest rocks in New Zealand and can be found in a number of places throughout the country, such as the Dun Mountain and Red Hills in east Nelson, the Takitimu Mountains in Southland, and Red Rocks on Wellington's south coast.
However landforms of recognisable volcanic origin are much younger, dating back to the Tertiary period (Miocene 24-5 million years ago) until present.
These volcanic areas and fields have played a major part in the shaping of New Zealand, especially in the northern part of the North Island (photo: Mt Egmont rises to 2518m (8261') above the Taranaki lowlands - NC).

Northland's eroded giant volcanoes
Between 25 and 15 million years ago a series of large volcanoes were active along both coasts of present-day Northland. Waitakere Volcano is estimated to have reached a height of 3000-4000 m (10,000-13,000') above the sea floor, and Kaipara Volcano was 60 km (37 miles) across at its base. Other remnants of these giant volcanoes now form the basement of Waipoua Forest, as well as the surroundings of Whangaroa Harbour.
More about the Waitakere Ranges

Northland Volcanic Field
Active in the last 10 million years, with the last eruption 60,000 years ago. Two main centres around Whangarei and Bay of Islands respectively. Mainly basaltic, but includes two large rhyolite domes (Parakiore and Hikurangi). Numerous basaltic scoria cones and lava flows.

Auckland Volcanic Field
  A basaltic vocanic field was active in the last 100,000-140,000 years below the isthmus, and produced 48 small volcanoes. The youngest and largest one is Rangitoto Island, built about 600 years ago.

Franklin Volcanic Field resulted from an earlier period of activity caused by the same hotspot, between 1.6 and 0.5 million years ago. Over 80 volcanoes were created, including the Pukekohe and Bombay Hills.
Read more about Auckland's environment and volcanoes.
Read more about the Auckland Volcanic Field at: Auckland Regional Council

Coromandel and Hauraki Volcanic Region
  This was the most active volcanic region of New Zealand between 18 and 4 million years ago. Activity started in the north (Great Barrier Island and Cape Colville) but later there was a continous chain of active volcanoes from Great Barrier Island to the Kaimai Ranges.
  Little Barrier Island is the eroded remnant of a strato-volcano that erupted between 3 and 1.5 million years ago.
Read more about the Coromandel Peninsula, and Little Barrier Island.

Waikato volcanoes
Pirongia and Karioi are the largest of a series of six basaltic and andesitic strato-volcanoes that were created between Raglan and Otorohanga between 2.7 and 1.6 million years ago.

Egmont Volcanic Field
Activity there started about 1.75 million years ago at what is now Sugar Loaf Islands. Mt Egmont/Taranaki is the youngest in the line of volcanoes that extends from there, and that includes the Kaitake and Pouakai Ranges. Mt Taranaki is an andesitic strato-volcano, similar to the Tongariro-Ruapehu group. It is about 120,000 years old, and its latest major eruption dates back to about 1755 A.D..
Read more about Mt Egmont at IGNS

Taupo Volcanic Zone
  The Taupo Volcanic Zone has been the location of most volcanic activity in New Zealand in the last 1.6 million years, and most of its geothermal activity. It extends from Ruapehu in the south to White Island in the North. Like other volcanic phenomena in the country it is the result of plate tectonic activity, that causes here the whole area to be sinking (graben).
   Beside the great volcanic cones of Tongariro National Park it includes domes such as Mt Tarawera and many smaller cones such as Mt Edgecumbe. It also includes two of the most productive calderas in the world, Okataina and Taupo.
Read more about: Taupo and Okataina volcanic centres at IGNS.

South Island intra-plate volcanoes
Otago and Banks peninsulas are the two main eroded remnants of a series of volcanoes that was active between 20 and 8 million years ago. Banks Peninsula started as an island off the east coast of the South Island, built successively by the two large Lyttleton, then Akaroa volcanoes. Sediments from the Southern Alps progressively filled the gap, and the volcanoes became a peninsula 20,000 years ago.

Visit dormant volcanoes and volcanic landforms
Click here to access Natureandco's Nature sightseeing/dormant volcanoes page
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