I've come to the conclusion that the only way to sit in a taxi in Tehran is sideways on the back seat.
Don't, whatever you do look forward and watch the maniacal, suicidal driving that surrounds you.
"They have no lane deescipline, thees peeples" said my interpreter. Understatement of all time

They weave across the freeway without any signalling, the fastest lane changes every mile, pedestrians cross the road when and where they please... On the way back to the airport (may Allah bless it) we were doing about 100kph and a group of labourers decided to cross the road on foot

; we had to brake and swerve to avoid pitching a couple over the central barrier.
In one traffic jam a pick up truck had stalled in the adjacent lane and was just rolling forward; the truck behind started to push it forwards and managed to bump start it amidst clouds of diesel fumes and much horn applause from those watching.
Two moped drivers were moving alongside each other at about 40kph one asking the other directions who responded with gestures and hand signals.
Intersections are complete mayhem

You'll see more courtesy on a bumper car ride. In fact, come to think of it I don't think I saw one vehicle without some damage.
There's probably worse cities... or are there?