Horeb

desert or mountain of the dried-up ground, a general name for the whole mountain range of which Sinai was one of the summits (Ex 3:1; 17:6; 33:6; Ps 106:19), etc. The modern name of the whole range is Jebel Musa. It is a huge mountain block, about 2 miles long by about 1 in breadth, with a very spacious plain at its north-east end, called the Er Rahah, in which the Israelites encamped for nearly a whole year. (See SINAI)

EBD - Easton's Bible Dictionary