You're looking into a bathroom, turn around and exit this bathroom and go down the hall to the right. Go to the door directly in front of you and you'll see a window above a table. And if you look to the right you'll see stairs going down. Go down these stairs. And at the bottom go to the left and go down the next flight of stairs. All the way to the bottom. You'll see two stairs to the left take two steps towards them and you've reached the end.