Decapolis in Fausset's Bible Dictionary

Thrice mentioned in Scripture: Mark 5:20, which shows that it was around Gadara (Mark 7:31; Matthew 4:25). A district containing ten cities, rebuilt, colonized, and granted special privileges by Rome 65 B.C. Other cities afterward receiving similar privileges cause confusion as to which are the original ten; probably Scythopolis (W. of Jordan), Hippos, Gadara, Philadelphia, Pella, Gerasa, Dion, Canatha, Damascus, Raphana (all E. of Jordan). The region once so populous is now almost without inhabitants, except a few living in savagery amidst the ruins and cavern tombs of Scythopolis, Gadara, and Canatha.