Hi Arunp,

I'm going London-2-Sydney this year and had the ferry in mind as well. But I changed plans, as soon as I heard that the ferry can be unreliable and therefore cause problems with the Turkmenistan transit visa. Instead, I'm now going Turkey-Iran-Turkmenistan.
(My thinking was: if I happened to be on a rush, at least "on the road" (meaning: no ferry), I'm pretty much in control of things. And crossing from Turkey through Iran will be just as good as the ferry in the worst case. Also: I'll enter Turkmenistan at Ashgabat, so less to ride in Turkmenistan.

If you like this route: Try David from Stantours.com for info on the Iranian visa for you. Not sure how Iran reacts to Americans these days.

Visas have been a nightmare, especially Turkmenistan: Every TKM embassy seems to have a different set of rules. I don't know anything about their US embassy, but within Europe: Brussels and Vienna offer the best/friendliest service.
Tajikistan and Kyrgyzstan Embassies were a walk in the park - very efficient. (You can read more about it in my blog's "paperwork" section: Panomoto *** Pan-Continental Motorcycle Journey )

You say you want to do it in a small car. This made me think of the "Mongol Rallye". Have a look at their website. Looks like good fun:
The Official Mongol Rally :: Mongolian Rally adventure on a stick

Another option for you could be: Tajikistan. Apparently there's a pass from Tajikistan to China, which opens 2 weeks per month. I couldn't find any info on wether it's possible to do for tourists, but maybe you can check with a Chinese agent.
(I'm going through Xinjang/Kashgar in China - send me an email and I can share my research on guides in Kashgar area).


Bjorn

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