In message , at 19:01:22 on Tue, 2 Apr 2019,
bob remarked:
Roland Perry wrote:
In message , at 20:57:41 on Mon, 1 Apr 2019,
bob remarked:
Ian Clifton wrote:
Let’s suppose you’re going from Reading to Hanwell. You might have to
make as many as 2 changes (at Slough, and Hayes & Harlington), to reach
a station you’d simply pass through if you didn’t change. What’s the
most such changes a (sensible & perfectly informed) passenger ever has
to make?

How about something like Thirsk - York - Peterborough - Stevenage - Welwyn
North?

Apart from there being a regular service from York to Stevenage, meaning
two changes eminently possible.

I obviously didn’t do my timetable checking properly, but I think the
concept is clear enough: Stevenage has a limited set of stations north of
Peterborough that are directly served, and Welwyn North has no direct
service to Peterborough, so pick a station up the ECML not served from
Stevenage with a station beyond not served directly by either Stevenage or
Peterborough, but where direct Anglo-Scottish services pass directly
through.

That only produces a fairly long list of 2-change scenarios. I think we
ought to be aiming for 3+

Journey planners also offer the occasional one-change, at Kings Cross.
Which goes back to my earlier question about how challenges like this
interact with doubling-back.

Doubling back makes finding examples much harder.

I'm wondering that (if allowed as a strategy) we might find
circumstances where it 'adds one' to the list.

--
Roland Perry