Apartment Corridor

On the left side of the image, the "corridor" between the two cylinders that formed the outer circle of the Herodium is visible.  In the lower level of this area were storage rooms, and in the upper were apartments that looked out over the landscape and over the inner courtyard

The Herodium was initially constructed to be a Palace/Fortress for Herod the Great (r. 37–4 B.C.).  It was a vertical cylindrical in shape with an outer and an inner wall.  Between the walls in the lower levels, there were storage rooms and in the upper levels, there were apartments.

On the exterior, there were three semi-circular towers and one taller circular tower that were situated at the four cardinal points on a compass.

In the lower interior of the cone, there was a bath, dining hall, garden, meeting spaces, and other structures.

The familiar "cone" shape of the Herodium was only added after the visit of Marcus Agrippa in A.D. 14 when Herod turned the site into his mausoleum.