County of Mason Real Estate View 2 listings HomeGuidesCounty of Mason Mason County is a county located on the Edwards Plateau in the U.S. state of Texas. At the 2010 census, its population was 4,012. Its county seat is Mason. The county is named for Fort Mason, which was located in the county. Guides San Antonio and the Metro AreasBandera / Pipe Creek / TarpleyBoerne / ComfortBulverde / Spring Branch / Canyon Lake / BlancoFredericksburgKerrvilleLa Vernia / FloresvilleMedina / MicoNew Braunfels / GruenePleasantonSeguinCounty of AtascosaCounty of BanderaCounty of BexarCounty of BlancoCounty of CaldwellCounty of ComalCounty of GillespieCounty of GonzalesCounty of GuadalupeCounty of HaysCounty of KarnesCounty of KendallCounty of KerrCounty of LlanoCounty of MasonCounty of MedinaCounty of Wilson