The aims of this article are to establish the extent of Vitruvius's knowledge of Athens, the other sources of his information on the city, and his preference for Hellenistic rather than Classical monuments. The following passages are analyzed: i, 6, 4, on the Tower of the Winds; ii, 1, 5, on a hut on the Areopagus; ii, 8, 9, on a wall at Athens which looks to Mt. Hymettus and Pentelicus, to be identified perhaps with the Long Walls between Athens and the Piraeus; iii, 2, 8, on the Olympieion; iv, 8, 4, on the Erechtheion and the temple of Athena Sounias; v, 9, 1, on the Colonnades of Eumenes II, on the shrine of Dionysos Eleuthereus, and on the Odeion of Perikles; vii, praef., 12, on the Parthenon and on the harbour of the Piraeus; vii, praef., 15, on the architects of the Olympieion; vii, praef., 16–17, on the telesterion of Eleusis and on the Olympieion. The conclusions are that, after having followed Caesar through Asia Minor in 47 BC, Vitruvius came back to Italy via the coast of Attica and probably stayed at Athens, and that his preference for Hellenistic monuments must be explained in terms of his education in the Hellenistic taste of Asia, and in particular of Hermogenes.