Vietnam / Cambodia travel advice needed

With the 31 days you have and the number of places you plan to cover during that period I doubt anyone will have any suggestions other than what you'd find in most travel guides.

I would have recommended Sapa in northern Vietnam near China but everything's booked. Ninh Binh would also have been nice - great scenery (think of oit as Halong Bay with ricefields rather than water)

Seriously, just buy a Lonely planet or Rough Guide and there's plenty of info in them. There's no hidden gems at any of the locations you've named that aren't in those books.

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Phil M. - Toronto, Canada
Time to kill? Then have a look at a few of my photos, including one published by National Geographic : http://www.flickriver.com/photos/phil_marion/sets/