"John Rowland" wrote in message ...
"Mark Brader" wrote in message
...

The lines swap vertically between
Chancery Lane and St Pauls, IIRC.
What is the reason for this?

This one *is* due to a narrow street above.

I don't understand, since the do-si-do clearly occupies a larger footprint
than would two tunnels running above each other.

I think it's the cathedral and the burial sites surrounding it - I
think the folks who built the original Great Central London Railway
stacked the tunnels because the authorities at St. Paul were afraid
that the digging might disturb or destroy the various gravesites
around the cathedral.

Besides, on the "Continuing your journey from" map, St. Paul's
Cathedral is practically next door to the station - I imagine that the
station builders got enough flak for placing the now-abandoned lift
shafts so close to the cathedral grounds, much less a tunnel.

Brad