How far apart are rail road tracks?

In minecraft each section of track takes up one block.

Be aware, you have to leave one block between rail linesor they will connect to each other.

For example, if you make a long rail road line between two villages and you want to have two rail road lines next to each other then you have to leave one block between the two or they will try to connect side by side. You make turn-outs or corners doing that.

If you go to the Minecraft WiKi you can find out how to make "switchable" turn outs, automatic switches and many other things with Redstone powder, and other items.