This is an historical part, introduced in the midst of Moses' sermon. On what account is not said: but it forms an interesting part, to intimate the progress of Israel's history. See Numbers 33:31-33. For an interesting account of Aaron's death, see Numbers 20:23-29.
Related Commentaries of Deuteronomy 10:6
Deuteronomy 10:6-7
6 And the children of Israel took their journey from Beeroth of the children of Jaakan to Mosera: there Aaron died, and there he was buried; and Eleazar his son ministered in the priest's office in his stead.
7 From thence they journeyed unto Gudgodah; and from Gudgodah to Jotbath, a land of rivers of waters.