A nationwide search is under way for a group of schoolchildren who buried a time capsule back in 1985.

All the participants were aged 10 at the time they put items in the capsule and are now hopefully approaching their milestone 50th birthdays. 

The telco giant is hoping the nearly 50-year-olds can reunite after 40 years to dust off the capsule and sift through a piece of Australian history.

So far, Telstra has only been able to track down one member of the group.

Telstra regional general manager Michael Patterson told 9news.com.au he wants the people of Australia to help the company find the other nine children.

“People move around all over the place, so we’re on the hunt to find these time capsule kids,” Patterson said. 

“These are young people from different schools across Adelaide, so they may not have ever come back into contact with each other.”

Patterson said Telstra has no idea what is locked inside the time capsule.

Though he hopes it might be a fascinating dive into ’80s technology and pop culture.

“In that era, they had the landline, they were using payphones… it wasn’t until two years later that the first mobile handset came out,” he said.

“We’ve since had the invention of social media, we’ve got artificial intelligence.

“The technology’s just evolving constantly.”

Telstra plans to crack open the time capsule on July 1 this year.