On the left of the northern gateway, just before the entrance, there was the Altar of Zeus Hippatos, where, as Pausanias noted, sacrifices were offered, but never blood sacrifices. This was in front of the East Porch, probably near the Altar of Dione, mentioned as being east of the southernmost column of the East Porch in the building accounts. The crypt below the Alter of Hippatos led into the main chamber of the temple, not far from where the statue of Athena Polias stood. Libations could be made to Athena Polias at the Altar of Thyechoos which was connected to her cella by the passageway under the North Wall. Others however have pointed out that as we do not hear of an altar to Athena inside the temple, these sacrifices may have taken place at the three known indoor altars.

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