Paul Scott wrote
Roland Perry wrote:
25 Jan 2010, Michael R N Dolbear remarked:

In some case this may involve crossing the street to a station
with a
different name or to a different part of the same rail or
underground
station but in all such cases Oyster must recognise that a jouney
is
not ending but continuing Thus for this purpose the Euston -
Kings
Cross - St Pancras interchange consists of three rail stations and
three underground stations (because of Euston Square) and the
Victoria interchange is two barriered rail stations - Victoria
(Southern) & Victoria (SouthEastern) plus an underground station..

I wouldn't use the Euston/KX example as there are other
complications,
and the three ticket halls at KX doesn't help either. The Victoria
example is sufficient.

Er.. I wouldn't use Euston/KX as an example as it doesn't seem to be
an
OSI...

According to the list that Peter Smyth posted on 09 Dec '09.

Euston (NR) - King's Cross (NR) (40)
Euston (NR) - St Pancras International (NR) (30)
But not
King's Cross St. Pancras Tube (LU)

Which complication /is/ a good reason for not using it as an example.

--
Mike D