Exodus 15,the Song of Moses and Miriam, the bitter water of Marah, the oasis of Elam.
There are two possible routes, the traditional route with Marah and Elim on the right side of the Gulf of Suez. The Manna was not yet given, the Israelis still had their provisions from Egypt, so Marah must have been only a few days journey from the Red Sea crossing.
The alternate route, favored by Muslims is to place the Red Sea crossing at the mouth of the Gulf of Aqaba, placing Mt Sinai in the Levant rather than the Sinai Peninsula. This would have posed major logistical problems for the Israelis, going all the way from Egypt to the Gulf of Aqaba with food from Egypt.