On Thu, 24 Jan 2008, Mizter T wrote:

On 24 Jan, 23:43, Arthur Figgis wrote:
Chris Tolley wrote:
Paul Scott wrote:

much as it might seem straightforward to have a London centred zonal
system spreading ever outwards, there will have to be a limit somewhere -
and it might as well be the Greater London boundary as anywhere.

Actually ... I rather like the idea of the zones spreading ever
outwards. With Zone 43 including the great arc of Wrexham, Chester,
Warrington, Manchester, Huddersfield, Leeds and Hull, it looks like a
one-zone ticket will be quite good value, though knowing the way that
such boundaries are set, I expect a Chester to Manchester via Knutsford
ticket would have to be a 2-zoner. ;-)

Some countries do have a national zone model, where you pay for the
zones you pass through. They use boxes or cells rather than concentric
rings as the zones.

This is how things are done in Tyne & Wear - see:

http://www.nexus.org.uk/ufs/shared/i...ne_Map_Col.pdf

The numbering logic behind the zones seems bizarre at first sight -
the zone numbers ascend in a sort of diagonal sweep from the south
west to the north east of the metropolitan county of T&W.

Surely north west to south east? Oh, you mean like a raster? Yes, i see -
the lines of the raster run SW-NE, and the raster progresses NW-SE.

The diagonal is basically the axis parallel to the Tyne, isn't it? At
least, the downstream reach. It's akin to Stanford's 'logical north'.

However I think it may be designed this was to make it easy to issue and
- crucially - verify the validity of tickets with zonal combinations
that are in a row or in a ring (think of a busy bus driver checking
tickets).

Yes, and each line in the raster has its own leading digit, with the
second digit increasing along it, so that the corresponding zones in each
line are adjacent. Although 58-60 are special cases: they should be 65, 66
and 75, respectively.

It'd be fun to do a version of that map coloured by the orthogonal
elements of the zone numbers; say, number 0x in red to 5x in violet, and
x3 in a pale shade to x9 in a dark one. Or with patterns of dots or
stripes instead of shade, so you can see at a glance how the coordinate
meanders across the map.

Note that the Tyne ferry has zone 38 all to itself.

39. I wonder which zones it counts as being adjacent to? Any which have
piers, i suppose.

The '4 zones in a ring' option is described as 'any 3 zones in a ring plus
one adjacent zone'; does that mean i could have three in a ring and one
touching just one of them? 56, 58, 59 and 60, say?

tom

--
I had no idea it was going to end in such tragedy