Commentaire sur Les Nombres 33:19

ויסעו מרתמה, “they journeyed from Ritmah;” this is the place of which the Torah wrote in Numbers 14,25: “tomorrow you will turn around and start traveling towards the sea of reeds.” This is what the Torah referred to when it wrote in Deut. 2,1: ונפן ונסע דרך ים סוף, “we turned around and journeyed in the direction of the sea of reeds.” From that point on they were detouring Mount Seir during all the way stations mentioned up until verse 36 of this chapter, where they were reported to have entered the desert of Tzin at Kadesh. Compare Numbers 20,1: “the entire congregation of the Children of Israel arrived at the desert of Tzin.”