List of London Underground stations
The London Underground is a metro system in the United Kingdom that serves Greater London and the home counties of Buckinghamshire, Essex and Hertfordshire. Its first section opened in 1863, making it the oldest underground metro system in the world – although approximately 55% of the current network is above ground, as it generally runs on the surface in outlying suburbs.
Source: Wikipedia — List of London Underground stations (CC BY-SA 4.0)