Adam Clarke on Genesis 35:21

Tower of Edar - Literally, the tower of the flock, and so translated Mic 4:8. It is supposed that this tower was about a mile from Bethlehem, and to have been the place where the angels appeared to the shepherds. The Targum of Jonathan expressly says: "It is the place in which the King Messiah shall be manifested in the end of days." By the tower of the flock we may understand a place built by the shepherds near to some well, for the convenience of watering their flocks, and keeping watch over them by night.