On their latest visit to Whanganui Ben and Aimee Bonne went straight from the airport to the top of Durie Hill Tower, to leave another padlock fastened to the railings.
It's become a tradition for the Auckland brother and sister, aged 16 and 14, to get off an Air Chathams flight only to climb the tower's 176 steps and leave a padlock engraved with family initials behind.
On their first trip they saw a lot of padlocks hanging off the railings. That's when they decided to add their own.
"We always put a lock up there, to leave our great memories up there. It's like bonding our love.
"We get our initials engraved at the jewellers, with the date."
Their grandparents Debra Hussey and George Munroe moved to Whanganui four years ago. The young people have visited for several days in every summer since - and sometimes more often.
At the start of their visit they make a list of things to do. As well as the tower there's Virginia Lake, driftwood at the beach, visiting family and going to 10 op shops.
"There's just everything you could want," Aimee said.
This visit they caught Vintage Weekend, and rode on a traction engine and in a steam train.
"We like checking out the trains, because we are train obsessors."
The padlock they left was brought from Paris, a city they visited with their parents last year.
"They're quite similar cities. They both have rivers. We thought it would be very fitting to bring it back to Whanganui," Ben said.
Their nana, Debra Hussey (nee McGrail), was brought up in Whanganui and has family here. She said Whanganui had been good to them, and was glad her grandchildren had responded to the move in such a positive way.
"You make the best of what you have. If it turns out great, you run with it."