The Queen is a woman "who smiles with her eyes" and relates easily to people from all walks of life, former Commonwealth secretary-general Sir Don McKinnon has told those at a service of tribute in Wellington.
Prime Minister Jacinda Ardern was among dignitaries marking the milestone of seven decades on the throne at St Paul's Cathedral in Wellington.
She was joined by the government's administrator Dame Helen Winkelmann.
Attention then shifted to representatives of the Defence Forces as they marched to the cathedral's altar.
The deputy Speaker, Cabinet Ministers, members of the diplomatic corps and members of the public were then formally welcomed to the service.
Bishop Duckworth reminded the congregation Elizabeth was just 25 when she became Queen, and during her 70 years of service "the world has changed dramatically".
"The Queen remains a symbol of our constitutional arrangements."
She has visited Aotearoa 10 times and laid the foundation stone of St Paul's Cathedral during her first visit, he said.
Former deputy prime minister and ex-Commonwealth secretary-general Sir Don McKinnon gave the keynote address, describing the Queen as "a remarkable woman" who was probably the most photographed person in the world.
He did not want to "upset the Buckingham Palace courtiers" with anything he said, recalling the regular meetings
He would always try to "have a laugh" with her and regularly discussed the All Blacks and other topics that would lighten the occasion.
"Her interests were far and wide" but talking about horses and cattle always engaged her interest.
"She had an immense knowledge of horse breeds all over the world."
This was a response he would expect from horse people everywhere, he said.
On Commonwealth Day a reception was always held at Marlborough House in London and he saw her genuine warmth and her ability to relate to people from all walks of life.
"Incredibly warm personality, very calm all the time, smiled with her eyes very vividly and serene when you think of all that was going on around her.
"Seventy years of grit, grace and glory," he said in conclusion.
Ardern did a short reading from an entry into Hansard in 1952 written by former prime minister Sidney Holland who attended the funeral of George VI, Elizabeth's father, and saw her write her signature as queen for the first time.
Holland observed in his Hansard entry that perhaps it was the start of a new Elizabethan era and Ardern said his words were prophetic as she has become the first monarch to be queen for 70 years.
The Queen had been staunch and a comfort during times of tragedy, she said.
It concluded with prayers and the singing of God Save the Queen.
The cathedral's bells rang as people left.
Overnight the UK began four days of pageantry, parties and parades to celebrate Queen Elizabeth's reign.
The first day included the traditional Trooping of the Colour and a flypast of 70 aircraft over The Mall and Buckingham Palace.
Senior royals joined the Queen on the palace balcony to watch the flypast.
However, at the end of the day the palace issued a statement saying the Queen will not attend a National Service of Thanksgiving at St Paul's Cathedral tomorrow because she was suffering "some discomfort" after a full programme earlier today.
The 96-year-old monarch has cancelled several appearances in recent months because of mobility issues.
