Organizers of Iran’s first international marathon say 28 Americans are among runners from more than 50 countries who have registered so far to participate in the April 7 race.
Officials on March 31 said women are invited to participate, provided they comply with Iran's Islamic dress code.
Women were barred from a local marathon in the city of Shiraz last year.
When U.S. President Donald Trump on January 27 announced a temporary ban on visitors from seven mainly Muslim countries, including Iran, the government in Tehran said it would block Americans from traveling to Iran.
But after a federal court halted the order in February, Tehran allowed a U.S. wrestling team to compete in Iran.
A revised order issued by the Trump administration on March 6 was also blocked by the federal courts.
The marathon will run through the streets of Tehran from Azadi (Freedom) Tower to the east of the city, organizers said.
More than 360 runners have registered so far, most from outside the country, and organizers say they hope the number rises to above 1,100.
Based on reporting by AFP and AP