Which building on the Acropolis was built around 421–407 BC?

• A. The Erechtheion in Athens
• B. The Parthenon
• C. The Propylaea
• D. The Temple of Athena Nike

Answer: (A)

Understanding when monuments on the Acropolis were built relies on both dating clues and distinctive architectural features. The Erechtheion fits the 421–407 BC window because its construction spans that late 5th-century phase of Athenians rebuilding the Acropolis after the Persian Wars, continuing into the early years of the Peloponnesian War. This temple is known for its irregular, multi-axial plan and the famous Porch of the Caryatids, reflecting adaptations to sacred sites and uneven ground rather than a single, symmetrical layout like the Parthenon or the gateway form of the Propylaea. The Temple of Athena Nike and the Parthenon belong to earlier or slightly different parts of the same period, while the Propylaea was completed earlier in the 430s BC. All of this places the Erechtheion squarely in the 421–407 BC construction window.