This is the first burial recorded in the Bible. Sarah was probably buried soon after she died. In the hot climate of Palestine, a body would quickly begin to decompose.
Burial caves were common in the biblical world. In Sarah’s case, a natural cave was used. But tombs were sometimes hewed out of solid rock (Isaiah 22:16). This is the type of cave in which Jesus was buried (Matthew 27:60).
Genesis 23:19 – 19 And after this, Abraham buried Sarah his wife in the cave of the field of Machpelah before Mamre: the same is Hebron in the land of Canaan.