Nice buzzfeed run down of all the tube lines in London, ranking them in order of usefulness. It's quite kind to most of them but being most familiar with the District recently this about sums things up for me: 8. District Line: ..A slowly trundling caravan of disappointment and crushed ambition.. The Victoria line was much higher until someone flooded a switching room with fast setting concrete the other day. via timeout

A great map here showing you whether it's actually quicker to walk between two underground stops than it is to take the train. There are a load of stations like this, probably down to the deep tunnels and escalators you need to travel to them. And of course, delays.

Just in time for the Olympics I got to take part in one of the quintessential experiences of London living by being trapped on the underground in the stagnant heat, between stations, during rush hour for over half an hour. I was lucky to have got on the last car so despite the hour it wasn't completely packed - I can only imagine the cattle car conditions at the front. There is literally no space in the tunnel beyond the tiny train - just pipes and one hundred year old tunnel. After half an hour of updates from the driver as to why we hadn't moved an inch (and increasing scoffs and grumbling from everyone) the train pushed forward a little until the drivers door was at the platform of the next station, whereby we all filed out by the drivers door. As I was leaving they shut the doors to the station, and hordes of irritated commuters stood around looking for a bus and loudly proclaiming - this would never happen in X (replace with your favourite city not holding the Olympics in a few days).