When Courtney Stevenson was 8-years-old, she wrote a message, sealed it in a sprite bottle and set it adrift.
The message floated from Shelley Beach in Picton to the shores of the Chatham Islands, where it was found by resident Richard Groomes 21 years after it was cast out to sea.
"It was quite fragile and falling to bits, so I took the plastic bottle home and cut it with a knife," Groomes told Fairfax media.
"It's been floating around for a very long time.
"I was surprised at how old it was - it could have been to Antarctica and back for all we know."
Stevenson was thrilled to hear from Groomes, who said he spends a lot of time on the beach.
"I even said to my dog that day 'I wonder when we're going to find a message in a bottle'.
"And bugger me, there it was."