Located about 15 miles north of Blythe just off US Highway 95, the Blythe Intaglios or Blythe Geoglyphs are large figures found on the ground that were created by scraping away layers of darker rocks to reveal lighter-colored soil. Carbon dating of the figures estimate they were created between 900 BC and 1200 AD.  They are best viewed from the air but can be seen from the ground as this pic shows.  The largest human figure is 171 feet long.

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