Under the step pyramid is a labyrinth of tunneled chambers and galleries that total nearly 6 km in length and connect to a central shaft 7 m square and 28 m deep. These spaces provide room for the kingâ€™s burial, the burial of family members, and the storage of goods and offerings. The entrance to the 28 m shaft was built on the north side of the pyramid, a trend that would remain throughout the Old Kingdom. The sides of the underground passages are limestone inlaid with blue faience tile to replicate reed matting. These â€œpalace faÃ§adeâ€ walls are further decorated by panels decorated in low relief that show the king participating in the Heb-sed. Together these chambers constitute the funerary apartment that mimicked the palace and would serve as the living place of the royal ka. On the east side of the pyramid eleven shafts 32 m deep were constructed and annexed to horizontal tunnels for the royal harem (The existence of this "harem" is debated). These were incorporated into the preexisting substructure as it expanded eastward. In the storerooms along here over 40,000 stone vessels were found, many of which predate Djoser. These would have served Djoserâ€™s visceral needs in the afterlife. An extensive network of underground galleries was located to the north, west and south of the central burial chamber and crude horizontal magazines were carved into these.
the link: [en.wikipedia.org]