Hello and thank you for downloading Witness from the BBC World Service.

I'm Simon Watts and today I'm taking you back to 1976

when archaeologists in Colombia found the ruins of one of the biggest indigenous settlements in the Americas.

The site became known as the Lost City.

It's 1976

top archaeologist Albert El Soto

flies into the remote mountains of the Sierra Nevada

the Santa Marta.

So I went in this helicopter... of the Sierra Nevada of Santa Marta.

So I went in this helicopter early in the morning,

and the light illuminates this archaeological site that was under the jungle but you could see from the helicopter stones

here and there in a magnificent way.

Albero stepped out into a huge site built by an Indian tribe called the Tyronas.

For nearly four centuries a city of terraces connected by intricate stone roads and staircases

had lain virtually buried in a remote valley.

The place is in a mountain and it's a very nice, it's like a garden, Plenty of water, streams all over it.

It's a paradise.

Until the 1970s,

Columbians didn't know they had Indian ruins to compare with the great Inca citadel of Machu Picchu in Peru or the Mayan temples in Mexico.

But the Spanish conquistadors, who first explored the country in the 16th century had spent a lot of time looking for gold,

and their accounts suggested the Sierra Nevada had once been heavily populated.

Is that all the coronado of the al-Tas-Cumres, all of the suscucullias. populated.

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