Situated underneath the Smithsonian, Athena has kept her palace away from mortal eyes. Underneath the American History Exhibit, it takes extremely good eyes to see 'Ἀθήνη' in a dim gray light. Only sharp mortal eyes and half-bloods can see it if they strain. Inside is a whole library filled with books, all up to the center piece, where her Aegis sits in all it's glory. Don't dare touch, though, because it's hexed to the max by electricity and other magic from Hekate, so don't touch it. The shield was made by the skin of Pallas' skin, the reason for Pallas Athena. Blueprints cover the walls of her office, which is near the entrance.