Comentario citado sobre Números 35:19

ויסעו מבית אל ויהי עוד כברת דרך לבא אפרתה, “they journeyed from Bet-El, and there still remained a tract of land before their arrival at Efrat, etc.” Efrat is another name for Bethlehem. The Torah spells this out in verse 19 where Rachel’s being buried is being described. Nachmanides explains that he personally had measured that the distance between the tomb of Rachel and Bethlehem is less than a mile. He concludes therefore that the commentators who want to derive the word כברת as stemming from כביר, “something major,” are in error. Yaakov could not have excused his burying Rachel there because the distance to Bethlehem was too great. The word כברת describes a certain land measure just as Rashi has said. The three letters ברת are root letters, the letter כ is not. The measure was one which was well known in those days.