In article , Richard J.
writes
Both the Waterloo and City and Snowdon Mountain Railway
are more expensive.

Not to mention Covent Garden to Leicester Square by tube, which from January
2004 will be £12.50 per mile if you buy a single ticket (non-Oyster).

Except your example isn't an end-to-end journey on a plausible route.
You could claim that asking a taxi to take you to the other side of the
street was £100 a mile, but that wouldn't prove anything useful.
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