The 72-year-old manages to clock about 50 kilometres every week and if he can cross the line this weekend, he'll become part of the elite group of runners to have completed the Canberra event 30 times. 

In recognition of the famous architect, runners are awarded the title of 'Griffin' if you've run 10 Canberra marathons, a 'Burley Griffin' after 20 and a 'Walter Burley Griffin' if you can somehow manage 30 finishes.

Mr Millett, who moved to Queanbeyan in 1957, said he was looking forward to receiving the Walter Burley Griffin Award.

"It'll be good to get there, to finally get the 30, and it's good that they've promoted it this way and this adds a lot of interest and I think it will keep bringing people back."

Mr Millett said while it is becoming more difficult these days, he's always enjoyed long-distance running.

"I've always liked running distances, I've done other things like mountain runs with groups of people too and I've always enjoyed that," he said.

"I've been doing marathons for around six decades now ... I've always run right through from when I was a kid at school and I've always been interested in athletics."

His interest in cross country running was sparked during his time at Queanbeyan High School and in 1976 he ran his first marathon at St Mary's in Sydney.

Mr Millett said he was simply hoping for the best on Sunday.

"I'm feeling apprehensive about it," he said.

"I'm not really what you'd call 'ready' because I haven't been doing great distances, but I find these days I need to recover after a run and it chops into your distances for the week."

He said the event had always been one of his favourites.

"I'm a member of the local cross country club and the veteran athletic club in Canberra and this marathon is one of the things we seem to do. It's a local event and you support it."