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Colosseum
Colosseum (Lair of Monsters)
Rome, Rome — Piazza del Colosseo, Rome, Italy
The ancient Roman Colosseum where the demigods battle monsters. The underground hypogeum still holds ancient threats connected to the mythological world.
landmarkReal-world locationlandmarkbattle-site
Visiting Tips
The Colosseum's underground hypogeum is now open to visitors on special tours. This is where Percy and Jason fought the twin giants.
Book Appearances
The Mark of AthenaBook 3
Percy and Jason battle in the Colosseum's underground hypogeum against Otis and Ephialtes.
Characters
Key Events
- ▸Battle against twin giants Otis and Ephialtes
Coordinates: 41.8902, 12.4922