Former paratrooper Norwood Thomas is embarking on the mammoth journey from Virginia, US, to visit his former beau whom he met just before D-Day while serving in London.
Thomas will travel for two days to reach Joyce Morris, who is now 88 years old, for a special trip Down Under, The Virginian-Pilot reported.
Norwood Thomas and Joyce Morris are to be reunited after 70 years
Thomas said: "I'd rather die traveling to Australia than live sitting around at home wondering, 'What if?'"
Morris was a 17-year-old British girl, whom Thomas remembers as a "pretty little thing," when he was a 21-year-old member of the US's 101st Airborne Division, the Associated Press reported.
Thomas told the paper: "Joyce was special; the one that got away.
"But after the war, my orders to go home came so quick there was no real chance to even say goodbye."
Norwood Thomas embarking on his journey to Australia
Thomas, who hasn't seen Morris since 1945, has kept a photo of her ever since.
After the war, the pair wrote letters to each other and Thomas even asked Morris to come to America and be his wife. But somehow Morris misunderstood and thought he'd found someone else. She stopped writing.
As time passed, the two went on with their separate lives. They both married other people, had careers and children. Thomas' wife died in 2001. Morris divorced her husband after 30 years.
Last year, Morris asked one of her sons to look for Thomas on the Internet, where he found his name featured in The Virginian-Pilot newspaper's D-Day series called "The Lucky Few."
Despite being nearly blind, Morris recently managed to reconnect with Thomas via Skype. After their story went public, hundreds of people made donations to help fund Thomas' trip to Australia, and Air New Zealand arranged the flight.
Thomas' son Steve said of the donations: "It's really touching, we want them to know it worked. He's going."
Norwood Thomas said he's excited to see his former love.
He confessed: "I'm just looking forward to seeing her smile.
"I have no idea if there'll still be romantic feelings.
"But at the very least, I'll get to spend time with an old friend. Just sitting and reminiscing will be wonderful."