The Parthenon is the largest and most important building on the Acropolis. It was the temple built for Athena Parthenos, the virgin goddess.

Part of the east frieze showing Athena seated and the
presentation of the peplos

Worship did not actually take place in Greek temples. They were built as a home to the statue of the god or goddess. Sacrifices and other rituals happened outside, around open-air altars.