By Penny Spiller
BBC News Online
Iran has one of the world's highest rates for traffic accidents and its roads can be quite a challenge, as people with experience of them have been telling BBC News Online.
Traffic in Tehran is often bumper to bumper
Around 22,000 people are killed each year with 400,000 crashes in 2002 alone.
Poor roads, unsafe cars and a blatant disregard for traffic laws by drivers are blamed for the high toll.
Despite government attempts to tackle the problem - introducing speed humps, traffic lights and one-way streets - driving in Iran remains hazardous.
Dr Ali Ansari, a lecturer in Iranian studies at the UK's Exeter University and fellow at the Royal Institute of International Affairs, said he would not drive on visits to Iran.
"I wouldn't take the risk," he told BBC News Online.
"There is a general lack of discipline among drivers on the roads."
He said he had seen drivers go the wrong way down one-way streets, and had even heard of road signs being removed.
Some of the problem appears to lie not with the roads themselves, but the driving culture.
"The infrastructure in general is poor but the roads themselves are not actually that bad," Dr Ansari said.
However, with many roads single-lane, "there's a lot of high-risk over-taking", he added.
Bumper-to-bumper traffic is a common sight in the capital, Tehran, where some two million cars fight for space on the roads. Four lanes of traffic are known to build up on three-lane highways.
However, another Iranian told BBC News Online the situation had improved a lot in the last two years.
Fines for breaking traffic rules and a greater police presence were factors, said the driver, who did not want to be named.
But many complain that - even with a new underground in Tehran - traffic remains intolerably heavy.
Another problem is that most cars in the city are locally-produced Paykans - Iran's equivalent to the 1960s Hillman Hunter. They are old, inefficient and do not use lead-free petrol.
It leaves Tehran, which sits in a basin surrounded by mountains, under a virtually permanent cloud of pollution - believed to cause the deaths of some 5,000 people in the city each year.
As well as trying to introduce a bit more discipline to the roads, the government has also set targets to phase out cars without catalytic converters.
But it remains to be seen whether such moves will help bring down the death toll.
"Iran is not an easy place to govern - it is used to moving at a frenetic pace," said Dr Ansari.