A propylaea means an monumental gateway in ancient Greek architecture. Entrance into the Acropolis was controlled by the Propylaea. Though it was not built as a fortified structure, it was important that people not ritually clean be denied access to the sanctuary. It was one of several public works commissioned by the Athenian leader Pericles in order to rebuild the Acropolis hill at the conclusion of the Persian Wars. Pericles appointed his friend Phidias as the supervisor and lead architect of this massive project, which Pericles allegedly financed with funds appropriated from the treasury of the Delian League. According to Plutarch, the Propylaea was designed by the architect Mnesicles, about whom nothing else is known. Construction began in 437 BC and was terminated in 432, when the building was still unfinished.
The Propylaea survived intact through the Greek, Roman and Byzantine periods. During the period of the Duchy of Athens, it served as the palace of the Acciaioli family, who ruled the duchy from 1388 to 1458. It was severely damaged by an explosion of a powder magazine in 1656, foreshadowing the even more grievous damage to the Parthenon from a similar cause in 1687. A Frankish tower, erected on the south wing, was pulled down in 1874.
The core is the central building, which presents a standard six-columned Doric façade both on the West to those entering the Acropolis and on the east to those departing. The columns echo the proportions of the columns of the Parthenon.
The Greek Revival Brandenburg Gate of Berlin and the Propylaea in Munich both evoke the central portion of the Athens propylaea.
References:The Odeon of Herodes Atticus is a stone theatre structure located on the southwest slope of the Acropolis of Athens. It was built in 161 AD by the Athenian magnate Herodes Atticus in memory of his wife, Aspasia Annia Regilla. It was originally a steep-sloped theater with a three-story stone front wall and a wooden roof made of expensive cedar of Lebanon timber. It was used as a venue for music concerts with a capacity of 5,000. It lasted intact until it was destroyed and left in ruins by the Heruli in 267 AD.
The audience stands and the orchestra (stage) were restored using Pentelic marble in the 1950s. Since then it has been the main venue of the Athens Festival, which runs from May through October each year, featuring a variety of acclaimed Greek as well as International performances.