The deconstruction of Christchurch Cathedral started yesterday with the arrival of a crane at the central city site - just as calls for its protection stepped up.
The Canterbury Earthquake Recovery Authority said the crane would be set up before any work started on the demolition.
Meanwhile, the Unesco World Heritage Centre joined calls for the cathedral to be saved from the wrecker's ball, saying that while the building was not a world heritage site, its symbolic value needed to be taken into account.
Spokeswoman Gina Doubleday said although the survival of the cathedral might appear to be expensive at first, saving it would help maintain the character of the city, bring it business opportunities and increase property values in the long term.
A restored cathedral would testify to history and continuity of cultural life that a brand new building wouldn't be able to convey, she said.
Emotions have run high since the Anglican Church announced this month that the beloved cathedral, which was badly damaged in the Canterbury earthquakes, could not be saved and would be "deconstructed" to just a few metres.
The Wizard of Christchurch has launched a campaign to save the cathedral.
The Wizard, Ian Brackenbury Channell, 79, has performed in Christchurch's Cathedral Square for decades and was distraught by the Anglican Diocese of Christchurch's decision to demolish the building.
He, and others, have called on Bishop Victoria Matthews to release engineering reports she says show the cathedral receiving major damage in the December 23 quake.
The cathedral has been extensively damaged in earthquakes over the past 18 months, with its spire snapping in half during the fatal 6.3-magnitude quake of February 22 last year.
Ongoing shakes have caused further damage to the building, according to the Anglican Church.
Ms Matthews has said it would cost more than $100 million to repair the historic building, while experts have said the reconstruction could be done for as little as $20 million.