 Starting about 2,000 years ago, the valley was inhabited by the Gabrielino (Tongva) Native Americans, who depended on the abundant game of the area for their sustenance.A major landmark for the Gabrielino was the Red Hill, located in present-day Tustin at the northern tip of the Cienega de las Ranas.The Gabrielino called it "Katuktu", "place of refuge".