<P> At some point in the valley's early geologic history, the water resurfaced and flowed into what is now the Colorado River . This created a luxurious plant life, forming a wetland oasis in the Mojave Desert landscape . </P> <P> Evidence of prehistoric life in Las Vegas Valley was found in 1993, when a group of construction workers discovered the remains of a Columbian mammoth . Palaeontologists estimate that the mammoth roamed the area some 8,000 to 15,000 years ago . </P> <P> Native Americans lived in the Las Vegas Valley, beginning over 10,000 years ago . Archaeologists have discovered baskets, petroglyphs, pictographs and other evidence in diverse locations, including Gypsum Cave and Tule Springs . Paiutes moved into the area as early as AD 700, migrating between nearby mountains in the summer and spending winter in the valley, near Big Springs . </P> <P> A trade caravan of 60 men led by the Mexican merchant Antonio Armijo was charged with establishing a trade route to Los Angeles . Las Vegas was named by Mexicans in the Antonio Armijo party . By following the Pike and Smith routes through a tributary of Colorado River they came upon the Las Vegas Valley, described by Smith as the best point to re-supply before going onto California . The travelers named the area "Las Vegas" which is Spanish for "The Meadows". </P>

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