Lazar Vukovic took on the 22km route in Belgrade on Saturday (April 21) in 24C heat and completed the race in two hours and nine minutes.
In doing so he’s raised £1,225 for disadvantaged children in Serbia - beating his target of £1,000.
He said: “The energy of the crowds and the music was just phenomenal.
“My goal was not to stop.
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“As I got to 18km I could feel my body closing down, but I had to carry on and finish for everyone who supported and of course for the charity. I didn’t want to let anybody down.
“I finished the half-marathon in 2h 09m which I’m pleased with considering I decided to run three weeks prior and only run recreationally.
“I’m looking at the time now as a benchmark as I do feel that I’ve caught the ‘bug’ and will be running in the future.
“I’d urge anyone who has an interest in fundraising for a cause or running a marathon as a personal goal to do so.
“The feeling is immense.”
Lazar has lived in Corby all of his life, having been born in Kettering.
His father was the rector of the Serbian Orthodox Church in Corby and his late mother was a governor of Hazel Leys Primary School.