In message , at 19:52:15 on Thu, 25
Jun 2009, Basil Jet remarked:
You could walk all the disused lines as well (or at least as much as
is possible)...

Aldwych, anyone?

London Bridge to King William St?

Borough to King William St, even.

The old line was never navigable all the way to Borough, and has
"recently" been cut through by the Jubilee Line. The only bit that's
continuous is the section I suggested (but last time I was there a wall
interrupted it approximately on the line of the southern bank of the
Thames).
--
Roland Perry