Newhall Newhall is the southernmost district of Santa Clarita, California. Prior to the 1987 consolidation of Valencia, Canyon Country, Saugus, Newhall, and other geographically proximate settlements into the conglomerate city of Santa Clarita, it was an independent but unincorporated town. It was the first permanent Anglo settlement in the valley. Newhall is home to the William S. Hart County Park, featuring tours of the famous silent movie maker's mansion.