<P> Various operative structures, plans and systems have been set up to prepare responses to volcanic activity within the urban areas, mainly coordinated in the' Auckland Volcanic Field Contingency Plan' of the Auckland Regional Council, which provides a framework for interaction of civil defence and emergency services during an eruption . Auckland also has a seismic monitoring network comprising six seismometers--including one 250 metres (820 ft) deep at Riverhead--and three repeaters within the region that will detect the small tremors likely to precede any volcanic activity . This is likely to give between a few hours and several days' warning of an impending eruption, and its approximate location . </P> <P> Auckland War Memorial Museum, itself built on the crater rim of Pukekawa, has an exhibition on the field, including the "Puia Street multi-sensory visitor experience", which simulates a grandstand view of an eruption in Auckland . </P> <P> In 2013, scientists said new studies showed Rangitoto had been much more active in the past than previously thought, suggesting it had been active on and off for around 1000 years before the final eruptions around 550 years ago . Civil Defence officials said the discovery did not make living in Auckland any more dangerous, but did change their view of how an evacuation might proceed . </P> <P> The volcanoes within the field are: </P>

When did the last volcano erupt in auckland