"Ian F." wrote in message
...
When buying rail tickets on line via whatever websites, is it possible to
specify 'Boundary Zone 6' as your start-point? I've never thought it
possible as I've never seen that as an option. Or does one just specify a
station in zone 6 to start from?

I think the logic is that it is not a BZ to/from wherever 'ticket'. It is a
BZ 'extension fare' used in conjunction with a ticket that you already have
in your possession.

An online site cannot determine if you already hold a suitable ticket to be
extended...

Paul S