Genesis 23:17-20

So Abraham bought the plot of land belonging to Ephron at Machpelah, near Mamre. This included the field itself, the cave that was in it, and all the surrounding trees. It was transferred to Abraham as his permanent possession in the presence of the Hittite elders at the city gate. Then Abraham buried his wife, Sarah, there in Canaan, in the cave of Machpelah, near Mamre (also called Hebron). So the field and the cave were transferred from the Hittites to Abraham for use as a permanent burial place.