Go Inside the Religious Epicenter of Iran

— -- Qom is Iran’s eighth-largest city, but its influence to the country both in its history and its future stretches far beyond the size of its population.

The city is considered the theological heart of Iran, and was the venue for the beginning of the Islamic revolution where Grand Ayatollah Ruhollah Khomeini spoke to massive crowds in the city’s main square.

Now Qom is widely known for its proximity to one of Iran’s nuclear enrichment facilities, which has brought the Iranian government sharp criticism as the U.S. continues efforts to roll back the country’s nuclear program.

ABC News’ Martha Raddatz visited Qom on the 36th anniversary of the revolution, she takes viewers through the city in the ABC Global Affairs digital original video above.