Which country has the largest railway network in the World?

United states of America has the largest railway network. For detailed statistical data about largest networks, see the link below:

http://timesofindia.indiatimes.com/home/sunday-toi/open-space/Which-country-has-the-largest-railway-network-in-the-World/articleshow/991607.cms

United states has the largest railway network in the world.
Can any one tell which state in India has largest railway station.