"Or perhaps in Slytherin,
You'll make your real friends,
Those cunning folk use any means,
To achieve their ends."
Speak the password to a damp stone wall in the dungeons and you'll find your way to the Slytherin Common Room. The Slytherin Common Room is underneath the Black Lake. Because of this, the light in the common room is green. Pure bloods are welcome in the Slytherin Common Room. Relax with Draco Malfoy and his minions as they discuss the lastest scheme against those pesky Gryffindors.
Enjoy your seven years at Hogwarts as a cunning Slytherin!
Comment with why you think I've placed the Slytherin Common Room here!