"I was very young and believed that people should have the right to leave their country if they wanted to," said the man, who called himself Hamid.
It was three years after the 1979 Iranian revolution, the country was at war with Iraq, and the borders were closed.
Hamid said he began smuggling people over the border to fund his own passage to the West.
Human smuggling and trafficking have now become huge industries in the field of international, organised crime.
But Hamid saw himself as a Robin Hood character who, far from harming anyone, allowed people a safe passage to opportunities they would never otherwise have been able to enjoy.
"I couldn't believe the way that some smugglers treated people. I did what I had to do to help people go where they wanted," he said.
His first clients were friends who could not afford what he described as an "expensive deal" through existing smugglers.
Using some of the connections he made in his own journey, Hamid developed a system for smuggling people to Pakistan, and from there to Europe.
He described how he would give his clients European passports stolen from tourists, and would bribe the passport control officials not to raise any objections.
"People used to say you could even get out travelling on a ration card just so long as the passport control guys had been seen to properly," he said.
His job was not without risks. In the past he has been attacked by bandits in the mountains and thrown in jail by the Iranian authorities.
Over the years, he says the reasons why people leave Iran have changed.
In the years immediately after Iran's Islamic Revolution, he said, they had political or religious reasons for leaving. During the 1980-88 Iran-Iraq war there was a flow of young male draft dodgers, followed by people fleeing the economic hardship generated by the conflict.
"Now it is mostly young men escaping Iran in order to go to universities and have a better education in the West," said Hamid.
But Iran is also home to a huge population of Afghan refugees, most of whom live in desperate poverty. Many are joining the throngs of young Iranians prepared to risk their lives in search of a better life.
Rahim Husseini is an Afghan who escaped the Taleban regime with the help of smugglers. His experience was so terrifying that at times, he said, he regretted leaving Afghanistan.
"Those who want to escape to Iran don't know the problems and hardship that they will encounter on the way. They are mesmerised by smugglers' promises. But after crossing the border, they will regret everything. The hunger, and the way the police treat Afghans, are too much to bear," he said.
"And if you don't have enough money, the smugglers will keep one of your relatives as a hostage until the debt has been paid."
The International Organisation of Migration says many migrants are also held hostage while their relatives try to raise the funds, or are forced into prostitution or begging.
According to refugee experts, the vast majority of asylum seekers arriving in Europe use the help of smugglers or traffickers.
For many Afghans - who have the means - smuggling is their only hope for a brighter future.