Mesa Verde, which translates as 'green table' in Spanish, is the biggest archaeological preserve in the US.
The ancient sites inside the 52,000-acre national park in Colorado were home to Puebloans, Native Americans of the south-west US, who during the 13th century chiselled entire villages out of the side of cliffs.
They did not leave behind any writings but the archaeological remains and oral stories passed down the centuries has meant researches have been able to piece together what life was like for them back then.
