Hades' Palace

Hades' Palace is the home of Hades, located in the pit of the Underworld. Percy visited this palace in The Lightning Thief, The Sword of Hades, and The Last Olympian. It's apparently modeled after the God's Palace on Mount Olympus since he is not welcome there.

Dreams
Percy dreams about the palace 3 times.

Rooms
The Throne Room- Hades sits upon a black onyx throne.