Easton's Bible Dictionary: M. G. Easton, M.A., D.D.
Trodden hard, or fastness, or "the waterless hill", the name of the Canaanitish city which stood on Mount Zion (Josh. 15:8, 18:16, 28). It is identified with Jerusalem (q.v.) in Judg. 19:10, and with the castle or city of David (1 Chr. 11:4, 5). It was a place of great natural strength, and its capture was one of David's most brilliant achievements (2 Sam. 5:8).