Such tombs were dug into the rock and were entered by a small doorway about three feet high. Inside was a cave-like room with shelves or benches carved into the wall. The body was placed on a shelf and after it decomposed, the bones were placed in a smaller niche.
From what we can gather from the Gospels, the body of Jesus was placed on a shelf near the entrance of a cave-like room. This was the room found empty on Easter Sunday morning, with only the burial linens lying there.
Why was such a large stone placed in front of Jesus' tomb? Because Pilate wanted to be sure that no one would move the body.
- Little Black Book, Diocese of Saginaw