The main failing of these trips is the very limited choice of tours. Most of them arrange package tours covering half a dozen major beauty-spots. Even for those who plan to travel independently, these rapid and superficial excursions are worthwhile since they enable you to gain a general impression, to spot places where you would like to spend more time, to get acquainted with traffic regulations and hotel procedure, and so on. Any driver with some experience of long-distance driving can take out without apprehension for Iran in any car in good mechanical conditions. He should have a small reserve of petrol, oil, and water and a couple of spare tires.
All itineraries converging upon Istanbul are good.
More than half the journey is carried out on motorways. Istanbul is about half way to Tehran form Europe. Travel in Turkey may seem a bit slow with its sharp slopes, sometimes harsh climate, long laps and mountain dwellers still well accustomed to tourists and motor traffic. Modern halts with sleeping facilities have been set up along the main itineraries. This solution is particularly convenient on the way back.