Acropolis with Athena Promachos by Phidias
On the Acropolis was a colossal bronze Athena, a memorial to Marathon, popularly called the Promachos though not in a striding, striking pose but at ease.
It was erected just within the gateway (the new Propylaea had yet to be built).
From tiny representations on Roman coins she seems to have been standing, perhaps with her shield at her side and with something on her outstretched right hand (an owl or Nike) - a prototype for the Parthenos.
The shield was decorated with a centauromachy which, Pausanias says, was designed by the painter Parrhasios and executed by the metal worker Mys.
If so it was in appliqué figures added to the shield later in the century, perhaps in emulation of the Parthenos.
Coin of Athens, Roman period
London, Cast

(Click the image for a full screen view)

Drawing with reconstruction

Boitte's reconstruction