Mr Preston (85) grew up in the Catlins and Mrs Preston (86) in Becks, before they independently moved to Dunedin in their teens to attend King Edward Technical College.
Like so many Dunedin couples, they met at a Joe Brown-organised dance in the Dunedin Town Hall.
"I was with a girlfriend and he walked over towards us to ask one of us to dance. My girlfriend said `I like the look of him'," Mrs Preston recalled.
"He was really nice. He still is."
While it is now obvious who caught Mr Preston's eye, he couldn't resist teasing his wife.
"I picked her because she was seven times a bridesmaid," he insists.
"I can only remember six," Mrs Preston added with a laugh.
The Prestons had four children before also adopting a Chinese daughter in 1964.
"We had room for one more," Mrs Preston said.
Mr Preston built their first family home in Stirling St, Andersons Bay. Later, they moved to Scotland Tce, Green Island, where they lived for 27 years.
"The Green Island years were fabulous. We had lots of kids around here all the time," Mrs Preston said.
They eventually moved to Gladstone Rd and, finally, Kinmont Cres.
"He built all our houses," Mrs Preston said with pride. "The only stipulation I made with this last one is that it had to be finished before we moved in."
Mr Preston has a simple recipe for a happy marriage.
"Never win an argument. Just go with the flow," he smiled.
"Never even try to win an argument," Mrs Preston added, with a giggle.
"Love, fun and laughter have been the key for us. We've always had good friends and neighbours wherever we've been, too, and that always helps. The kids have been the mainstay, though, I think."
The Preston extended family reunited for a party at the Royal Hotel in Green Island on Saturday night to celebrate the anniversary.
"We felt like Prince William and Kate, with all the kids taking photos," Mrs Preston said.
Which is not surprising, for among the many congratulatory cards they received this week was one from Queen Elizabeth, on behalf of the Royal Family.
"We get our next one when we get to 100," Mrs Preston joked.
