The dark, musty dungeons below the school. Who knows where all they lead?

A tower just over top of the Entrance to the school. It's the tallest in Hogwarts and used mainly to observe the stars at night.

Located in the West tower. Come here to send owls to the ones you care about... or just need to speak to.

If you take the door to the right of the great staircase and tickle the pear in the fruit basket painting, it will become a door knob. Open it and you will be lead to the kitchens directly below the great hall. The House Elves are contantly at work!