There were concerns the event will suffer backlash after Washington in December accused North Korea of launching a cyberattack on Sony Pictures to block the release of The Interview – a Hollywood film depicting the assassination of Kim Jong-un.
But U.S. marathoners appear to be taking it in stride. "About 25 percent of the people we take to North Korea are Americans, and for the marathon it's even more," said Cockerell. "This doesn't affect tourism."
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Marathoners can choose to do a full marathon, half-marathon or a 10 kilometer race. En route to the finish line, they will pass a number of renowned North Korean monuments including the Arch of Triumph, the Eternal Life Tower and the People's Army acrobatic theater.
"You get a medal for a top-three finish, and every finisher gets a certificate, Cockerell said. "If you win the pro-marathon, there is a cash prize as well."
This year's event also comes with humanitarian perks – for every person that signs up to run the marathon through Koryo Tours, the company will donate 365 packaged meals to North Korean orphanages.
But for some, the highlight is to finish in the Kim Il-sung stadium, which will be packed with 50,000 cheering spectators.
"I know it's bizarre, but I may run the marathon with my friend," a British citizen residing in Singapore who wished to remain anonymous told CNBC. "The thought of finishing before the crowd in Kim Il-sung stadium is incredible."
"My wife isn't so happy about the idea though, so I haven't booked anything yet," he said.