Kuala Lumpur, 1998. It was there that the Bothwell bowler claimed pairs gold for Scotland alongside Joyce Lindores.
The 57-year-old is now gearing up for her fifth successive Commonwealth Games, having been named last week in the 10-strong squad of men and women who will represent Team Scotland at Glasgow 2014.
"Don't say I'm an old pro - I'm young at heart," says Letham, whose impressive tally of Games appearances is matched by Alex Marshall. "It's amazing to think this is my fifth. I remember back to my first in Kuala Lumpur in 1998 and that seems like yesterday."
Since then she has competed in Manchester, Melbourne and Delhi. On those occasions the medals were not forthcoming, something Letham looks forward to rectifying as she steps out to play on the greens at the Kelvingrove Lawn Balls Centre this summer. To that end, the world outdoors fours champion said she intends to make the most of the opportunity to play on home turf in the coming months.
"We are taking every advantage we have to practice on these greens," she said. "We will know every blade of grass."
Scotland have won 28 lawn bowls medals, including 13 gold, in previous Commonwealth Games, but the team returned empty-handed from Delhi in 2010.
In Glasgow each bowler will compete in two out of four events: singles or fours and pairs or triples. With Bowls Scotland head coach David Gourlay having pledged to keep those details under lock and key until June 12 to maximise tactical advantage, Letham is also tight-lipped.
"I think it's good," she said. "We all know what positions we are playing in but David has decided for tactical reasons to keep it under wraps and let everybody wonder. We are not surprised but perhaps some of the opposition will be at the outcome."
Letham will form part of an experienced Team Scotland, which as well as Marshall who holds a record 19 world titles, includes international open singles champion and world No 1 Paul Foster.
Foster from Troon, Ayrshire, who competed in Melbourne and Delhi, said it felt "unbelievable" to be selected for Team Scotland, especially after a tough couple of months in which he faced an unspecified health scare. "It was something personal but it is all sorted out now," he said. "I'm on the mend and feeling 100% again. It is good to be back because it was a worrying time. I'm raring to go. I feel better in myself and have actually lost half a stone. I go out walking a lot now. I have a bike, go to the gym and I watch what I'm eating. So within myself, I am well prepared."
The 41-year-old, who won Commonwealth Games pairs gold in 2006, said he believed Scotland's biggest threat in the bowls arena in Glasgow would come from the southern hemisphere, chiefly Australia and New Zealand.
"They are always there or there about and have fantastic teams," he said. "England too. They are always hard games but at the end of the day, I don't worry about my opposition, I worry about myself. I know that if I can perform in whatever discipline I'm in, then I will have a chance."
In addition to any edge gleaned from getting to know every inch of the Kelvingrove greens, Foster reckons the weather gods could also lend a helping hand.
"Coming from Scotland we are used to the rain and maybe other countries might not like it, like the Australians who are used to the sunshine all the time," he said. "We are used to playing in cold winds and heavy rain as well as sunshine so that could be an advantage to us."
Gourlay said it had been an extensive and demanding selection process that lasted more than 18 months, with the final team being "full of achievers" who had consistently succeeded on the world stage.
"We have a baseline target of two medals, but I firmly believe if we perform we'll exceed that target," he said. "This is our best-prepared bowls team and we look forward to being part of what we believe will the most successful Games for Team Scotland."