The temple of Demeter, sometimes called ὁ μυστικὸς σηκός, or τὸ τελεστήριον, was the largest in all Greece, and is described by Strabo as capable of containing as many persons as a theatre. The plan of the building was designed by Ictinus, the architect of the Parthenon at Athens; but it was many years before it was completed, and the names of several architects are preserved who were employed in building it. Its portico of 12 columns was not built till the time of Demetrius Phalereus, about 318 BC, by the architect Philo. When finished, it was considered one of the four finest examples of Grecian architecture in marble. It faced the southeast.