In message , at 13:44:13 on Fri, 27
Jun 2014, tim..... remarked:
I didn't think the TfL journey planner would stretch out as far as
Cambridge (well, Ely really, I'm only starting in Cambridge because
the Sunday service from Ely has let me down).

Neither did I but I guessed you might have used it and therefore tried it
and surprised myself (and you too no doubt).

It always used to surprise me that you could buy tickets from
Underground TO to places, like Cambridge, well outside of London based
upon there being "barrier" free interchange at Finsbury Park [1]

I always took that for granted, having grown up in the 60's living in
Chelmsford and being able to buy a ticket to there, from a London
Underground station. I don't know to what extent that was a result of
the cross-platform interchange at Stratford, or whether it was a more
general capability.
--
Roland Perry