On Sun, 7 Jan 2007 14:17:54 -0000, "Raymond Kirk"
wrote:

wrote in message
Interesting site. This section should help the OP.

http://www.trainweb.org/tubeprune/vi...20diagrams.htm

--
gordon


thanks for that. I find it confusing! Can someone please explain it to me in
laymans terms.

In essence there are lengths of track that run on beyond the normal ends
of the platforms at both Brixton and Walthamstow. There are protective
signals / switch points to stop a train in the overrun tunnels reaching
the normal platform areas.

Where it says "pit" then there is a sunken area under the rails which
would allow access for a train technician / fitter to the underside of
the trains.

At Walthamstow the tunnels run for a considerable distance - I
understand that they almost reach to Wood Street station but I don't
know how close to the surface they reach or whether the remain at the
same depth as at Walthamstow Central. I don't know how far they go
beyond Brixton station.

I think the telephone symbols indicate the existence of a signal post
telephone which the driver could use to speak to the line controller.

There certainly used to be a scheduled move into and out of the tunnels
at Walthamstow as I used to catch a train that came out of the overrun.
It was novel watching people's faces when a train arrived from a
completely unexpected direction. If trains become defective but can
still be moved then sometimes they will be shoved into the overrun
tunnel until such time as it is easier and less disruptive to take the
train back to Seven Sisters to get into Northumberland Park depot. I
understand engineer's trains have been parked in Victoria and Brixton
sidings in recent days.
--
Paul C


Admits to working for London Underground!