American runner Charlie Barkowski had everything lined up ahead of what would’ve been his 52nd marathon on Friday. He had a flight picked out; his hotel was ready; he looked forward to revisiting some of the same cafes and sites he had seen in 2013 when he first traveled to Iran. On Tuesday, however, Barkowski, who currently lives in Greece, learned he wouldn’t be getting a visa for his second trip.

“I was literally ready to go to the airport and get my visa in Athens,” the 35-year-old told The Washington Post on Friday, just hours after what was being billed as Iran’s first marathon in Tehran had concluded.

“It was kind of sad,” he said, noting that because he remained on the email list of participants he had seen photographs of the event, as well as the medals each entrant received. “I’m sorry I couldn’t participate.”

Barkowski was one of 28 Americans who had registered for the race, but according to the Associated Press, other than one Iranian-American, it appears no other U.S. citizens were able to obtain visas.

Barkowski was never given a reason that the Iranian government didn’t issue him a visa, which he applied for in January. He theorized it could have something to do with the executive order President Trump signed this year that placed a temporary ban on citizens of Iran and several other Muslim-majority countries from receiving U.S. visas.

Barkowski said he noticed right away that the process to apply for a visa had changed since he had gone through it in 2013. In addition to the standard forms, Barkowski said he had to provide five years of work history, as well as a note from his employer. (Barkowski blogs for a discount travel website called Boarding Area.) Barkowski said Iran’s government also required exact details of his flight, which it didn’t in 2013 when he applied for and received a visa.

“Something changed,” he said, noting when he first applied for his latest visa he was told it would take no more than three months to process. He was also assured that because he was traveling to the country for an athletic event, the process should go even more smoothly.

“[Race organizers] said they felt comfortable” because the Iranian government had signaled it “wanted to bring in more athletes,” Barkowski said.

That theory was put to the test just after Barkowski applied when Iran was faced with the decision of whether to issue visas to a group of U.S. wrestlers that would allow them to compete in an international tournament in the country. Initially, the government barred the group from competing, directly citing Trump’s initial executive order signed in late January, but following a U.S. District Court judge’s decision to block the president’s order in early February, the Iranian government relented and issued the wrestlers visas.

In the meantime, however, Trump signed a revised executive order in early March that kept the temporary ban placed on Iranian citizens, as well as citizens from five other majority-Muslim nations. That order, too, is being challenged in court.

“It could’ve been the executive order,” Barkowski said about why his Iranian visa application was declined.

Barkowski doesn’t know for sure, and neither does Sebastiaan Straten, the lead organizer of the race run by a group called I Run Iran.

“No explanation was given by Iranian authorities for not issuing visas for American and U.K. runners that we applied for,” said the Dutchman, who also runs a travel agency.

“Even having an Iranian visa in your passport does not guarantee entry in Iran,” he added in an email. “I had a visa but could not attend my own marathon event. Fortunately, many runners did, about 300 from 42 different countries, including some with dual [Iranian and] U.S. and U.K. nationality.”

Iranian government officials did not immediately return The Post’s request to comment.

The AP identified at least one Iranian-American who ran the race on Friday, which was won by Iranian Olympian Mohammad Jafar Moradi.

Amir Arasta, a chiropractor based just outside of Washington, D.C., told the AP he was “disappointed” U.S. runners without dual citizenship couldn’t participate, but called the race “a dream” for himself.

“I always thought this would be the best route, from Azadi Sports Complex to Azadi Square,” he said, describing the 26-mile course that wove its way through the center of the city. “When I heard it would be happening I was very happy.”

It was the route that had Barkowski excited to participate, as well, although he expressed reservations about earlier assertions from Iranian government officials that the marathon’s female entrants would be segregated and have to run indoors due to restrictive laws in the country that pertain to women, including that they compete not just separately from men, but in a space where men can’t even see them.

“I thought what a shame that they were not going to be able to participate on the same streets [as the men],” he said.

On Friday, however, race organizers received permission to allow women participating in the event to run outside, although they were instructed to still cover their bodies head-to-toe, save for their faces as Iranian law requires.

Despite the race’s faults, Barkowski on Friday remained adamant that he wanted to run in Iran if ever allowed back in. He recalled his past trip to the country fondly, noting that most of the people he met there were friendly toward him.

“Many of the people I met there love Americans,” he said of his 2013 trip. “Every time someone heard my American accent, they wanted a picture.”

He said the only time he felt any hostility was at the airport when he was going through customs.

“The passport people and police were the only ones that gave me some weird looks,” Barkowski said, chalking it up to “a government thing.”

“Who knows what a year will bring,” he added.