Editor’s note: This story contains disturbing images. Viewer discretion is advised. Port Kaituma, Guyana (CNN) — Dark storm clouds broke to reveal a dense Amazonian rainforest outside the ...

In the sixteenth century, Sir Walter Raleigh began his search for El Dorado in Guyana's rainforest. Four hundred years on and a group of young adventurers from the UK - the Serious Explorers - are ...