The Propylaea. The monumental gateway of the Acropolis was designed by the architect Mnesikles and constructed in 437-432 B.C. It comprises a central building and two lateral wings. The colonnades along the west and east sides had a row of Doric columns while two rows of Ionic columns divided the central corridor into three parts. The walls of the north wing were decorated with painted panels or wall paintings and that is why it was called the "Pinakotheke". The ceiling of the Propylaea had coffers with painted decoration and a perforated sima around the roof.