Visa-You just get it on the border (and a very small one!). If you go to an embassy they will think its for the whole country and might not issue it.
Visa Cost - I thought it was going to be $10 but it was free for me as a New Zealander. However it is only for the Kurdish Area.
Weather - I was sick of the cold in Iran (it was snowing!) hence my choice to go through Iraq, lower mountains means it will be warmer and I was right! Its a bit nippy at night but its fine. I didnt have enough time to go into the mountains as I was meeting a friend in Turkey. But I would have loved to go up there, but then again I hate being cold and damp on the bike....
If you cross into Iran after that - it will be cold! Even Turkey was freezing! In fact I didnt warm up until I got to Ethiopia (Feb 2012)! Thats when I shed all my winter gear that was given to me during my time in the Kurdish areas (Iran & Iraq)
If you have more questions just ask!
Oh I just thought of something... USD are acceptable everywhere - i found it hard to find cheap acc. in big towns because they normally go with the whole family so they need a suite - like a mini apartment. I managed to find one for $40
You can not take cheap fuel from Iraq into Turkey. I normally carry spare fuel, but for once I wasn't (lucky me) while crossing into Turkey I saw everyone
(Turks and Iraqi's) was getting their fuel confiscated off them.
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