Most metros have logos or symbols to mark their station entrances, rolling stock, and printed matter such as maps or tickets. Since most metros around the world are indeed called ‘metros’ (only few are called subway, underground, U-Bahn, T-bana or something else), many metro logos are more or less fancy variations of the letter M. [link]
Check out this awesome collection of Metro Logos from around the world:
For more Metro Logos from Around the World visit: http://mic-ro.com
