Joanne Selby was just ten when she wrote to her gran Janet from the campsite where she and her family were staying.
It should have taken just a couple of days to reach its destination 258 miles away.
But instead it took three decades.
Sadly, Janet had passed away by the time the pristine postcard landed on the mat of her former home last week.
But Joanne, now 41, is delighted it has finally turned up.
“I don’t remember sending it or writing it, to be honest.
“I do remember the holiday. We had a lovely holiday, the weather was perfect.
“My gran was on her own and she only had myself and my sister as grandchildren. We used to keep in touch with her by postcard when we were away because she did not have a telephone.
“So it is not a surprise that I did write a postcard but I had no idea that it had not arrived. It is a surprise it is looking so pristine.”
The card, which has a picture of Nefyn beach on the Llyn Peninsula in north Wales, was sent to Mrs Selby in Chester-le-Street, Co Durham.
And the message on the back from the excited youngster, who was then aged 11, says: “Dear Gran, We are right at the top of the campsite with fantastic views of the bay with mountains behind it. Just like being abroad.
“We have been to the beach, club, shops and restaurant. They are all just down the road. See you soon, love Joanne.”
The 12p stamp is green with a little Welsh dragon in the corner.
Joanne, from Glasgow, was thrilled to see photos of the postcard after it was finally delivered.