From BiblePortal Wikipedia

Coelo-Syria [1]

hollow or depressed Syria; Syria in the vale, 1Ma_13:10 . This name imports the hollow land, or region, situated between two long ridges of mountains; and those mountains have been always understood to be Libanus and Anti-libanus. As these ridges run parallel for many leagues, they contain between them a long, extensive, and extremely fruitful valley.