At least 11,000 people were in attendance. Among them are Key, Governor-General Anand Satyanand, diplomats from Australia and the United States and Pike River Coal chief executive Peter Whittall.

Key assured grieving families at the packed Omoto Racecourse, that four million New Zealanders were mourning with them, and had prayed for them since news of the disaster broke.

Now families should take solace in the fact the men were in good spirits on the day they went to work for the last time, he said.

Grey District Mayor Tony Kokshoorn talked of hope for the families of the dead, turning from optimism, to anxiety, anger and grief, saying "tears will flow for years to come".

Local poet Helen Wilson, read a poetic tribute to the dead, saying the disaster had stopped life in Greymouth, but now Coasters must remember the dead and "what it is to be alive".

Mourners arriving for the service had filed slowly past 29 tables each containing the name of the one of the 29 miners and contractors who died in the mine explosion before taking up a spot on the grass or in the grandstands.

Tim Mora, the vicar of the Cobden-Rununga Anglican church, told the service it was a time of mourning not just for the West Coast but for the whole of the country.