I have been wondering about this for sometime, and I have finally got'n off my ass and research a bit...It is possible to travel pretty much around the world by freighter/cargo ship...
I have found a great resorce for this kinda adventure with a very informative FAQ section, I unfortunatly will prob not get to travel this way because of the time it takes to get from one port to another, but if this can help even one person try this interesting way of travel, then my time was worth it, I will live the experience through you!!!
...Check this Site
Freighter Travel
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