Aidan Stanger wrote:
As BR was also developing the InterCity market, and new railways were
being planned for other cities (such as the Newcastle Metro) it seems
pretty certain that you're wrong. Anyway, London wasn't entirely free
of
closures - the Broad Street line closed, and if there hadn't been a
change of leadership, Marylebone would probably have closed.

Some BR-era closures in Greater London:

Harrow & Wealdstone - Belmont (1964){- Stanmore Village originally
(1952));
West Drayton [& Yiewsley] - Uxbridge (Vine St) (1962);
West Drayton - Staines West (1965);
Nunhead - Crystal Pal HL (1954);
Woodside - Selsdon (1983);
Dalston Jct - Broad Street (1986);
Finsbury Park - Ally Pally via Cranley Gdns (1954);
East Brixton (1976);
Navarino Road curve and Camden Road - Primrose Hill (1994?)

Not that many really when compared with other parts of the country -
Aberdeenshire for example (of course the population of Aberdeenshire is
much less), and when you take into account reopenings such as Dalston
Junction - Stratford, Thameslink tunnel, ELL extension (we hope) and
new build: Jubilee line Baker St - Stratford; Victoria line (entire),
DLR (part-reopening and part new build), Croydon Tramlink (ditto).

KenS