Genesis 23:17 - The cave of Machpelah.

And the field of Ephron which was in Machpelah, which was before Mamre, the field, and the cave which was therein, and all the trees that were in the field, that were in all the borders round about, were made sure

This cave within the field of Machpelah was purchased by Abraham as a family sepulchre. It is the resting place for Abraham and his wife Sarah, his son Isaac and his wife Rebekah, his grandson Jacob and his wife Leah (Genesis 25:9; 49:31; 50:13), and perhaps others. The location of the cave is believed to be below the Haram el Khalil mosque, also called Abraham's mosque.