The ceremonies started on Sunday morning at 9:33 am local time (0603 GMT), the time when the late founder of the Islamic Republic Imam Khomeini arrived back home on February 1, 1979 from exile.
Meanwhile, a special ceremony is underway at Imam Khomeini’s mausoleum in Tehran, which is attended by thousands of people from all walks of life as well as a host of senior state and military officials.
Simultaneously, special ceremonies are being held in more than 80 Iranian cultural centers in 60 countries to mark the first day of the Ten-Day Dawn period.
Imam Khomeini spent more than 14 years in exile, mostly in the Iraqi holy city of Najaf. He also spent some time in Turkey and France, before his return to Iran.
On this day, Ayatollah Khomeini was welcomed by millions of people who had converged on the capital Tehran from across the country. His arrival intensified popular protests against the US-backed Pahlavi regime, leading to its downfall ten days later.
The day when Imam Khomeini returned to Tehran marks the start of 10 days of celebrations better known as the 10-Day Dawn festivities, which culminate in nationwide rallies on February 11 this year, the anniversary of the triumph of the Islamic Revolution.
Earlier this week, Leader of the Islamic Revolution Ayatollah Seyyed Ali Khamenei visited the mausoleum of the late Imam Khomeini to pay tribute to the founder of the Islamic Revolution.
Iranian President Hassan Rouhani and members of his cabinet also visited the mausoleum of the late Imam to renew their allegiance to the ideals of the founder Imam Khomeini. They were accompanied by the Imam's grandson, Seyyed Hassan Khomeini.
The Iranian nation toppled the US-backed Pahlavi regime 35 years ago, ending the 2,500 years of monarchic rule in the country.
The Islamic Revolution spearheaded by the late Imam Khomeini established a new political system based on Islamic values and democracy.
During the 10-Day Dawn festivities, Iranians take part in different events and activities to mark the victory of the Islamic Revolution.
