Piraeus (Greek: Πειραιεύς): main port of ancient Athens.
- Originally a rocky island, losely connected to the mainland; the muddy flats that connect the rock to the shore of Attica gradually become more accessible
- The part known as Munichia was fortified in the late sixth century BCE by the tyrant (sole ruler) Hippias, who needed a garrison to back up his position
- The new peninsula offered three excellent ports: Kantharos, Zea, and Munichia; in the course of the fifth century, they replaced Phaleron, which had been the main port of Athens in the sixth century. The city is designed on a Hippodamian plan.
- In 483, Themistocles initiated the ship building project that would make Athens great; he was also responsible for chosing Piraeus as main naval base. It was connected to Athens with Long Walls.
- During the Decelean War (413-404), the Spartan admiral Lysander blocked the Athenian ports and starved the city into surrender. The Long Walls were destroyed.note[Xenophon, Hellenica 2.2.20.]
- In the next year, there was fighting between the pro-Spartan regime and the democrats.note[Aristotle, Constitution of the Athenians 33-40.]
- In 393, Conon restored Piraeus; as trade center, it had remained important anyhow.
- In the Hellenistic age, Munichia was often garrisoned by the Macedonians to keep Athens in check.
- Piraeus, the second settlement in Attica after Athens, was sacked by the Roman general Sulla in 88 BCEnote[Appian, Mithridatic Wars 30-41.] but remained importantin the Roman period.
- The port was used in 324 CE by Constantine the Great in the civil ware against Licinius.note[Zosimus, New History 2.22.2.]
- It was also sacked by Alaric, the leader of the Visigoths, in 395 CE.