DynamicSpirit
Established Member
The Waterloo and City Line which serves Waterloo and the old city at Bank. The Northern Line which serves north of the Thames (though named in anticipation of the Northern Heights extension plan). The Bakerloo Line whose name is a portmanteau of Baker Street and Waterloo which the was built to connect and originally called the Baker Street & Waterloo Railway. The Central Line for running through the centre of London opened under the name of Central London Railway. The Metropolitan Line (built as Metropolitan Railway) derived from the world metropolis, a term used to refer to London in the old days. The District Line was originally the Metropolitan District Railway. Jubilee and Elizabeth Line are the exceptions here because they were named in relation to Queen Elizabeth, the longest serving monarchy of the UK.
You can add to that: The Piccadilly line serves Piccadilly Circus, the Circle line refers to how the line circles around London central London, and the most recent example of a new name - the Hammersmith and City line - connects (surprise!) Hammersmith with the City. Allowing for that the District and Metropolitan lines would have been understood as somewhat geographical when they were first named, I would say the only underground line whose name isn't at least a bit geographically helpful is the Jubilee line.