The Mark of Athena

Camp Jupiter

Camp Jupiter (Roman Demigod Camp)

The Argo II arrives at Camp Jupiter. Tensions rise between Greek and Roman campers before the quest begins.

Colosseum

Colosseum (Lair of Monsters)

Percy and Jason battle in the Colosseum's underground hypogeum against Otis and Ephialtes.

Pantheon

The demigods pass through the Pantheon area while navigating Rome on their quest.

Piazza Navona

The demigods navigate through Piazza Navona during their exploration of Rome.

Tiber Island

Isola Tiberina (Island of Healing)

Referenced as a place of ancient healing power connected to the Roman gods.

Castel Sant'Angelo

The fortress plays a role in the demigods' navigation of ancient Rome's mythological underside.

Underground Rome

The Athena Parthenos Chamber

Annabeth follows the Mark of Athena through Rome's underground tunnels, defeats Arachne, recovers the Athena Parthenos, and falls into Tartarus with Percy.

Great Salt Lake

The Argo II encounters Phorcys and Keto near the Great Salt Lake during their eastward journey.

Georgia Aquarium

Percy and Frank visit the Georgia Aquarium and are trapped by Phorcys and Keto, who run the aquarium as a front for imprisoned sea creatures.

Fort Sumter

The Argo II stops in Charleston. Annabeth, Piper, and Hazel visit the city's historic areas and encounter a trap.

Strait of Gibraltar

Pillars of Hercules

The Argo II reaches the Pillars of Hercules. Jason and Piper must negotiate with Hercules to pass through into the Mediterranean.