The skene was placed at the top of the orchestra area, most likely first in
wooden form and later in more permanent stone. The Theatre of Dionysos shows
how this addition took semi-permanent form. Adjoining the rims of the earliest
orchestra-circle is a rough stone foundation pierced with slots. These presumably
carried uprights for a wooden skene façade. Most archaeologists would
date this foundation at about 450 BC, this is, roughly about the time of the
production of the Oresteia. Literary references suggest that these
type of semipermanent structures survived in use for some considerable time.
Dismantled when the dramatic festivals were over, it permitted the use of the
area for other purposes.
The circular pathway that surrounds the orchestra is called the parodos and can be accessed from either side of the skene. Serving two primary purposes, the parodos is an important element of the Greek theate. First, it provides the audience with a way to access their seats. However, more importantly for the purpose of staging the play, it provides access to the chorus and some actors to the orchestra. The chorus never entered the orchestra from the skene. Characters returning from a journey, such as Agamemnon in Agamemnon or Theseus in Hippolytus would probably also make use of the parodos.
From the Oresteia onward
almost every tragedy makes use of a door in the skene as a means of entry and
exit. The door was presumably central, and must have been quite large. Most
of these tragedies are set in front of Greek houses or palaces, know as the
oikos. The foundations of such houses can still be found throughout Athens but
little archaeological evidence is left of their facades, the part of the house
which the audience would see. Fortunately, many vase-paintings depict homes
of deities or legendary characters, and the earliest instances go back to the
sixth century. All the buildings in such cases are shown in the likeness of
a temple porch. It is therefore widely believed that the façade of the
oikos resembled a temple.

There is also reason to believe that, on the stage in front of the central door,
stood a permanent scenic altar, as distinct from the cult altar. This altar
would probably be a simple fixture that could be used when required by the action.
It could have been used for Jocasta’s prayer to Apollo in Oedipus
the King. It was anonymous enough, also, to stand for other objects in
special cases, such as the tomb of Agamemnon in the Libation Bearers
or of the late Pharaoh in Helen, and perhaps for the rocky projection
on which Oedipus first sits in Oedipus at Colonus.
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