Documentary AreaSimply the best Documentaries

Deep in the Bolivian Andes at the height of 13,000ft stands Tiwanaku, the awe-inspiring ruins of a monolithic temple city. Built by a civilisation who dominated a vast swathe of South America, it was abandoned 1,000 years ago. For centuries it has been a mystery - how did a civilisation flourish at such an altitude and why did it vanish? Jago Cooper journeys through Bolivia's spectacular landscape to investigate the origins of Tiwanaku and finds evidence of an ancient people with amazing understanding of their environment, whose religion was based on collective effort and ritual beer drinking.

The very heart of Africa is covered in dense tropical rainforest. The animals that live here find the most ingenious ways to carve out their space in a claustrophobic landscape. Danger lurks in every shadow, but some animals thrive here, from honey-stealing chimps to birds with a lineage as old as the dinosaurs, thundering elephants and kick-boxing frogs. Here in the Congo, no matter how tough the competition, you must stand up and fight for yourself and your patch.

The Milky Way, our galaxy, is a magnificent sight in the night sky, but we know surprisingly little about it for certain. What is its shape? How many stars does it actually contain? What lies at its centre? The Gaia space telescope will answer these questions, being armed with the most advanced camera to leave our planet, and it will allow us to see our galaxy as we've never seen it before. The Sky at Night visits the factory in Chelmsford that made the astonishing sensor at the heart of the mission.

North Koreans cross the border into China illegally every year, some via a modern-day underground railroad to freedom and eventual citizenship in South Korea. VICE visits the most dangerous place in the world: Kashmir's line of control, which partially occupies the Indian state and separates India from Pakistan.

In episode two, we discover the golden age of the La Tene Celtic warrior and reveal how their world extended as far as central Turkey. But by the middle of the first century BC, the Celts were under threat from an expanding Roman Empire, and the Gallic warrior Vercingetorix would challenge Julius Caesar in an epic battle that would shape the future of Europe.

The Internet is an uncontrollable labyrinth of content and imagery that operates under loose laws and partial anonymity - a new frontier where people can do anything and see anything, whether they should or not. In this lawless landscape, who's in control? The protectors? The abusers? In this episode meet the content moderators who watch the worst of the Internet so you don't have to; a convicted hacker whose punishment was the virtual prison of the unplugged; plus, a blackhat hacker who encrypts and holds computer files hostage.