Mountains: Sinai
Source: TTT
Exodus 19:2
After they had set out from Rephidim, they entered the Wilderness of Sinai, and Israel camped there in front of the mountain.
Exodus 18:20, 23
Teach them the statutes and laws, and show them the way to live and the work they must do. / If you follow this advice and God so directs you, then you will be able to endure, and all these people can go home in peace.”
Exodus 31:18
When the LORD had finished speaking with Moses on Mount Sinai, He gave him the two tablets of the Testimony, tablets of stone inscribed by the finger of God.