In article , Rupert Goodwins
writes
If you have a Z1/2 travelcard, there are a set of rail lines you can
travel on, forming a closed area around Central London and a set you
can't. Where's the island.

I can go up to Hampstead on the Northern Line, or to Archway. both
north of Hampstead Heath.

Hampstead and Archway are on the Z2/3 boundary.

Archway is north-east, not north.

In fact, I can get to stations by rail
north, south, east and west of Hampstead Heath,

There's no station north of Hampstead Heath in zone 2.

If you mean 'a zone is anything that London Transport says it is',
then yes, zones is zones. But if you look at the map, then zones is a
pattern of concentric fare stages,

Right. But they aren't completely convex.

Hampstead Heath is a tweak. A hack. Every station around it is in zone
two, no matter what direction you go in or how you go there.

Not true. You can draw a reasonable-looking boundary between zones 2 and
3 with no odd loops or "islands".

Aside
from Willesden Junction, also on the NLL, every other station on the
network connects either with stations in its own zone or in a
subsequent zone.

Huh? I don't get what you're saying here. There are other stations with
no neighbours in the same zone. If you mean that they're the only
stations whose neighbours are both in the same zone different from that
station, then this might be right (what about Acton Central, though?).
But that's because it's orbital, not radial, and close to a zonal
boundary.

It breaks the spirit and the practicality of the zone system,
Rubbish.
Well, by that argument you might as well run a zone boundary pseudopod
down to Kings Cross and move it into zone two.

You could, but it's been chosen not to.

Zone 1 got extended south of the river by quite a way; it used not to
be. What about all the Z2-4 users who lost out by that change?

The principle that *is* being applied is to not allow long runs in a
single zone. I can find exactly two places on LU outside Z1 where you
can go 6 stops within one zone (that is, if you get on at station number
1 with a single-zone ticket, you can take a single train to station 7
and be able to exit with that ticket). The NLL zone 2 section was 17
stops long; after the changes the pieces in zone 2 are 0, 4, and 9 stops
long. You can do 8 stops on GOBLIN, and that's it.

--
Clive D.W. Feather, writing for himself | Home:
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