The actual known location of the Ravenclaw Common room is unknown. It is believed to be located in a tower, but it is unknown whether Ravenclaw has it's own tower. Some believe the common room is located in the turret of the astronomy tower, but that rumor is widely debated. Others believe Ravenclaw has it's own tower, but yet again, this is a hotly discussed opinion.
What is known of the Ravenclaw Common room is that it is circular in shape, decorated with the house colors (blue and silver in movie, blue and bronze in book). The fact that the room is circular brings forth the debate that the common room is located in a tower.
The common room is also rumored to have a statue of founder Rowena Ravenclaw herself. It is theorized that the statue was constructed by someone other then Rowena herself, as Salazar Slytherin is the only known member to create a giant statue depicting themselves.
Instead of requiring a singular set password, ravenclaw common room has many. The door to the common room is decorated with a large eagle head door-knocker. Upon arriving at the entrance, the knocker asks the witch or wizard to answer a riddle. If answered correctly, the door will open, if not, the student must wait for another student to answer correctly.