This question thoroughly depends on where you are. The best possible thing you could do would be to mapquest or googlemap your search from your very address.
how long does it take to travel by boat from vitnarm to australia
When Saigon fell in '75.
how long will it take a small boat from england to Greece
About a 3 or 4 hour flight from a 1970's era jet airliner.
depends on the boat, a long time!
See Communist Vietnam website.
Not long if you are in Cambodia and have a passport.
How long will it take to get to Amsterdam from new york on a boat
depents from where the boat journey will start
Depends on the type of boat and where you're starting from:
It depends on the speed of the boat
a long time