London Underground
LondonUnited Kingdom
The Underground (a subway to those who don't know) is the easiest and fastest way to travel while you are in London. The fares are cheap and you will feel the hustle and bustle of big city London. The Underground is deep under the ground and for those scared of heights I wouldn't recommend looking down while you are on the escalators taking you up.
Here's an online version of their famous map:
Reviewer: Publisher
Tag: London, Entertainment