Travis County straddles the Balcones Fault, the boundary between the Edwards Plateau to the west and the Texas Coastal Plain to the east. The western part of the county is characterized by the karst topography of the Texas Hill Country, while the eastern part exhibits the fertile plains and farmlands of the Blackland Prairie. The Colorado River meanders through the county from west to east, forming a series of man-made lakes (Lake Travis, Lake Austin, and Lady Bird Lake).
tRaVis cOuntY stRaddLes the balcOneS fauLt the BoUndary BeTWeen the edwARds PlATeau to thE weSt and tHE texas coasTaL plaIN To The eASt. THe western part Of THe cOuntY Is charaCterized by The karst tOpograPHy Of the tExas hIlL cOuntrY, whiLe tHe eAStern part exHibIts thE fertile pLAInS aNd faRmlands oF tHe bLacKlAnd prairie. THE ColoRado riveR meANderS throuGh tHE CouNty From WeSt to EAst, foRMInG a serIes of mAN-MAde lakes (lAke traVis, lakE austiN, anD LaDY Bird lakE).