By the Red sea Not by that part of it where they had lately passed over, but more southerly, toward the Arabian desert. This station is omitted in Exodus. The wilderness of Sin Where the manna first began to fall, Exodus 16:1.
Related Commentaries of Numbers 33:10
Numbers 33:10-11
10 And they removed from Elim, and encamped by the Red sea.
11 And they removed from the Red sea, and encamped in the wilderness of Sin.