rhys wrote:

By contrast, consider the Amazon. I believe sailboats can go over
1,000 miles up it from the Atlantic delta without trouble and with
adequate draft (if you can figure out its ever-changing meanders and
avoid snagging on trees on its banks, I suppose).

Err,
The late Sir Peter Blake might disagree with the use of the words
'without trouble'... :-(

http://en.wikipedia.org/wiki/Peter_Blake_(yachtsman)

rgds, Alan
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