On Jan 9, 10:27*pm, Recliner wrote:

6. Many tube stations were used as air-raid shelters during the Second
World War, but the Central Line was even converted into a fighter aircraft
factory that stretched for over two miles, with its own railway system. Its
existence remained an official secret until the 1980s.

Sounds interesting!

10. The longest distance between stations is on the Metropolitan line from
Chesham to Chalfont & Latimer: a total of only 3.89 miles.

Really? Only 3.89?

19. Over 47 million litres water are pumped from the Tube each day, enough
to fill a standard leisure centre swimming pool (25 metres x 10 metres)
every quarter of an hour.

That is a vast amount.

34. The total length of the London Underground network is 249 miles.
116. The total number of stations served on the network is 270.
133. An interactive novel has been published, set on the London
Underground. Two five three can be seen he London Underground. “253” can
be read here.

Are the figures in 34 & 116 still up-to-date? What is the 253 about?

39.One of the early names proposed for the Victoria Line was the Viking
line.

They might have expanded on this: VIctoria-KING's Cross.

69. The Underground has the oldest section of underground railway in the world, which opened in 1863.
74. The first Tube tunnel was opened in 1880, running from the Tower of
London to Bermondsey.

I suppose the first example was cut-and-cover.

79. Penalty fares were only introduced in 1994.

"79. Penalty Fares were introduced as recently as 1994."

103. According to a 2002 study air quality on the Underground was 73 times
worse than at street level, with 20 minutes on the Northern Line having
"the same effect as smoking a cigarette".

I remember this report which seems to have been totally buried.

112. There are 14 journeys between stations that take less than a minute on
average.

I imagine these are all in zone 1.

126. The River Westbourne was funnelled above a platform on Sloane Square
in a large iron pipe suspended from girders. It remains in place today.

I mistakenly thought it was the Tyburn.

134. In cockney rhyming slang, the London Underground is known as the Oxo
(Cube/ Tube).

News to me!

143. A series of animal shapes have also been highlighted in the London
Underground map, first discovered by Paul Middlewick in 1988. They're
created using the tube lines, stations and junctions of the London
Underground map.

Discovered?