Tube station proximity map
Tube Proximity is a mapping tool I've developed that places circles round the locations of tube stations on Google Maps. It can give you an approximation of walking distance to each station and an overall view of how London is covered by the underground network.
It's built using the Google Maps v3 api, which has improved the speed of drawing shapes on overlays considerably. Previous attempts to complete this project have been hindered by slow rendering times, although even now an older computer might take a second or two to generate the circles.
The geographic data for the locations is taken from an existing freedom of information request to TFL. If some of the stations seem misaligned its because the lat/long pin-point the ticket hall, not the station entrance. Also Overground line stations are not in the data.
Looking at the map there are some interesting things to note: The north-west is served particularly well by the tube network. This area was commonly known as Metro-land in the earlier part of the 20th century and was given good links to city for commuters. In contrast south London has very few stations, sometimes attributed to the geology of the ground in the area, but most likely the result of it already having a good overground network by the time the tube was gaining popularity.