In article , Paul Weaver
writes
Looking at the history of the tube, the vast majority of it was built
between 1890 and the first world war. Obviously this was all
entrepreneurs, capitalists that produced the finest public transport
system of its day.

Whats happened since the end of the second world war? Nothing.

Quite a lot.

But you should actually be comparing before- and after-1933, when the
system was nationalised.

New lines since 1933:

Central: all the bits east of Liverpool Street, and the West Ruislip
branch, were planned in the late 1930s and opened after WW2.

H&C: service between Aldgate East and Barking started in 1936.

Jubilee: Baker Street to Finchley Road tunnels opened 1939 (the private
sector having failed to do anything about this bottleneck). The line
south/east of Baker Street is all 1979 or later.

Metropolitan: four-tracking north of Harrow-on-the-Hill and
electrification beyond Rickmansworth are 1960s.

Northern: the bits north of Archway were opened in the late 1930s or
early 1940s.

Piccadilly: Heathrow extension is 1970s & 1980s.

Victoria Line: built in the 1960s.

On a similar note, what geological problems are there preventing massive
tube expansion?

There's so much stuff at medium depth that new lines have to go much
deeper, possibly below the Blue Clay.

--
Clive D.W. Feather, writing for himself | Home:
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