Two ancient sites in Athens. Ancient Agora of Athens has 5 tickets and tours to book; Roman Agora of Athens has no online ticket listed. The table and the two notes below put them side by side; the full pages have what to see, the ticket and the timing for each.
The Ancient Agora of Athens was the civic heart of the classical city, the square below the Acropolis where citizens voted, traded and argued, and where Socrates taught. It holds the best-preserved Doric temple in Greece, the Temple of Hephaestus, and a museum in the fully rebuilt Stoa of Attalos.
The Roman Agora of Athens is the marketplace built with money from Julius Caesar and Augustus in the last decades BC, a short walk east of the older Greek Agora. Its star is the Tower of the Winds, an octagonal marble clock tower that survives almost complete. The site is small, central and quick to see.