Interislander's Aratere is heading towards its final journey - as work is underway to get rid of the Cook Strait ferry's decaying dock.

Infrastructure is needed for new ferries, arriving in 2029, and work to demolish Aratere berth will in the coming months.

It'll spell an end to the ageing ferry's operation because it can't use other Interislander docks.

NZ Herald political editor Thomas Coughlan unpacks this announcement.

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