Sylvia Baxter reached the milestone on Tuesday and will celebrate the occasion with her loved ones and more than 100 guests at a big party tomorrow.
Mrs Baxter (nee Lorentzen) said she was the first one in her family to reach the milestone.
"People ask me — ‘What do you put it down to?’
"Well, I had carrots and potatoes for a meal for many years of my life," she said, laughing.
To the amazement of her family, she was still living on her own and while she had "all sorts of things going wrong" with her health, her memory was intact.
Mrs Baxter could easily recall the details of her upbringing in the Deep South.
Her Danish father and English mother migrated to New Zealand with their two children for work.
Twelve years after the birth of their second child, Sylvia was born in Invercargill.
She was raised during the Great Depression, which were "tough times."
"A lot of children went to school hungry, with patched clothing, or walking barefooted. That wasn’t me — I was lucky.
"But you know what? Because everyone was on the same level, you understood and you helped out and shared because you knew everyone was struggling in the same way — it is a bit different now."
Changes in the nature of the community and the ongoing development of technology were the biggest changes she had seen in her life, Mrs Baxter said.
In the past she had known every one of her neighbours, but now many people had no clue about who they were living alongside.
"Whenever you walked up and down, you’d meet someone on the street and stop and have a conversation.
"Now everyone is only looking to their mobile phones. It is sad."
She loved going to school and learning about everything, Mrs Baxter said.
At 15, she started work as a shorthand typist at the former Kew Hospital, where she stayed working in a range of roles for about 40 years.
She also volunteered for various organisations such as the Citizens Advice Bureau and victim support charities.
She married her beloved Eric in 1949, several years after he came back from World War 2.
He was her brother-in-law’s brother and they spent about six years corresponding by letter.
The couple had two sons, Neil and Craig.
She now had four grandchildren and countless great-grandchildren, whom she had to admit she had lost count of, Mrs Baxter said.
Looking back, she felt lucky as she had lived a life full of love and happiness.
"I’ve had ups and downs like everybody in their life.
"But I think I’ve been very fortunate in the people I’ve known and met over the years and people have been really kind to me. I feel very lucky."
