London Underground : Extremely hot, clammy and urine-scented in many cases. Trains range from modern and shiny filth pits to dilapidated and flea-riddled filth pits. Mice are present on tracks and platforms. Very crowded at peak times, although not as bad as Tokyo.

Technological achievement : the newest line sports trains so smooth you can hold a cup of coffee without spilling it.

Biological achievement : a new species of mosquito has evolved (over 4,000 generations) that has no light-sensitive organs and can survive on minimal moisture, and can even hibernate for extremely extended periods of time. Was introduced into the tunnel environment during the Blitz.

Financial achievement : Travelling on the tube is more expensive per mile than Concorde.

Tip for new users : Although there is a £10 fine for failing to carry a valid ticket when attempting to exit a station, you can bribe the desk staff quite easily. I have successfully done so at Seven Sisters station. (Usually I carry the correct ticket, but I somehow managed to cross zone lines).