"James Christie" wrote in message
...



With difficulty, because GPS has an accuracy of +/- 100m, unless of course
you are using Differential GPS, but that is mainly a maritime system.
--

It's been somewhat better than that for a while, since the "random error"
was removed. IME the error is probably nearer 2 metres. Though the powers
that be can reintroduce the random factor, or turn it off entirely, should
they feel the need.

G