Help on Bash - Windows, Setting directories for cygwin

[Weasel F. Subs]

I've recently reinstalled cygwin (downloaded the packages on December 
19), with bash as one of the packages, but I'm no longer able to read 
the directories such has "/home", "/usr", "/bin" and the like.
Example:

   bash-3.2$ cd /home
   bash: cd: /home: No such file or directory

Is there a way that I can change this? Could you reference to part in 
the manual that tells how this can be done?

Windows XP Professional, Sp2

Cygwin installed on "c:\cygwin". "/cygdrive/c" does work.
bash is located in /cygwin/bin.