Migdal Eder (biblical location)
Migdal Eder, literally, "Tower of Eder" in Hebrew, is a tower mentioned in the biblical book of Genesis 35:21, in the context of the death of Jacob's wife, Rachel. The biblical record locates it near the present-day city of Bethlehem.
So Rachel died, and she was buried on the way to Ephrath (that is, Bethlehem), and Jacob set up a pillar at her grave; it is the pillar of Rachel's tomb, which is there to this day. Israel [Jacob] journeyed on, and pitched his tent beyond the tower of Eder. (Gen 35:19-21 NRSV)
Many have attempted to identify the exact location of the tower, but early sources differ on the location.
Connection to the Birth of the Jewish Messiah
Scholars interpret Micah 4:8 as a prophecy indicating that the Messiah would be revealed from the "tower of the flock" (Migdal Eder) which is connected with the town of Bethlehem, southeast of Jerusalem.
And you, O tower of the flock,
hill of daughter Zion, to you it shall come, the former dominion shall come,
the sovereignty of daughter Jerusalem. (Micah 4:8 NRSV)
But you, O Bethlehem of Ephrathah,
who are one of the little clans of Judah, from you shall come forth for me one who is to rule in Israel, whose origin is from of old, from ancient days. Therefore he shall give them up until the time when she who is in labour has brought forth; then the rest of his kindred shall return to the people of Israel. And he shall stand and feed his flock in the strength of the Lord, in the majesty of the name of the Lord his God. And they shall live secure, for now he shall be great to the ends of the earth;
and he shall be the one of peace (Micah 5:2-5 NRSV)
Mishnaic sources indicate that animals "found" (that were kept?) in the fields within a certain distance from Migdal Eder were subject to being used as sacrificial animals in rituals of the Jerusalem temple.