Harold Riley’s 'one of a kind' portrait of Nelson Mandela

In 1967 a biologist began listening to strange sounds recorded way out at sea, he realised it was whales and that they were singing. Claire Bowes has been talking to Dr Roger Payne about the discovery that helped change people's perception of whales and helped found the modern conservation movement at a time when whales were close to extinction. (Photo: Humpback Whale, courtesy of Christian Miller of Ocean Alliance)

7 Joulu 201711min

In December 1917 Finland proclaimed its independence. For many centuries it had been controlled by its powerful neighbours, Sweden and Russia. As World War One raged across Europe and Russia was embroiled in its own revolution, Finnish intellectuals took the opportunity to push for their own state. But many ordinary people were more concerned with dire food shortages and the chaos caused by conflict. Olga Smirnova hears memories of that time.(Photo: 1917: A Communist base burning during the Finnish civil war. Credit: Getty Images)More personal stories from history of independent Finland can be found at the Finnish Institute in London http://www.taleoftwocountries.fi/frontpage/

6 Joulu 201710min

In 1967 the British withdrawal from their colony of Aden led to the creation of the People's Republic of South Yemen. Britain had colonised the port city in 1839. Aden had been at the centre of the British colonial trading system and had been one of the busiest ports in the world. The handover has been described as one of the most chaotic in British colonial history. Farhana Haider has been speaking to the former British diplomat, Oliver Miles and to Ghassan Luqman who says the scars of Britain's quick withdrawal are still being felt in Yemen today.Photo: Aden 1967 Copyright: Alamy.

5 Joulu 201710min

The four huge granite heads of former presidents on Mount Rushmore have become one of America's most famous monuments. Construction started on the site in 1927, led by sculptor Gutzon Borglum. His granddaughter Robin Borglum Kennedy speaks to Lucy Burns about his work.Picture: Mount Rushmore, June 1995 (KAREN BLEIER/AFP/Getty Images)

4 Joulu 201710min

Thousands of scientists moved to deepest Siberia to dedicate their lives to research. The Soviet authorities began building the city in 1957. Academics were enticed there by the promise of housing and interesting work. Olga Smirnova spoke to Dr Victor Varand who made his life in Akademgorodok, or Academic City.Photo: Scientists at work in Academic City. Credit: Victor Varand.

1 Joulu 20179min

Alexander Litvinenko was a former colonel in the Russian secret service, but fled to London seeking political asylum when he became critical of the Putin government in 2000. In November 2006 he was poisoned with the highly radioactive substance Polonium 210. Rebecca Kesby has been speaking to his wife, Marina, about his life and excruciating death.(PHOTO: Alexander Litvinenko in a London hospital a couple of days before his death in November 2006. Credit Getty Images.)

30 Marras 201710min

In November 2002, an oil tanker, the Prestige, sank off the coast of Galicia in north-west Spain, causing one of the worst environmental disasters in the country's history. In the following months, thousands of people from all over Spain travelled to Galicia to help clean up the spill. Simon Watts talks to Xavier Mulet, one of the volunteers.(Photo: Volunteers cleaning up after the Prestige. Credit: Xavier Mulet)

29 Marras 201710min

Colonel Domingo Monterrosa was one of El Salvador's most successful and ruthless military commanders in the fight against leftist rebels. But in October 1984 the rebels carried out an audacious plan to kill him. Mike Lanchin has spoken to one former rebel and a war correspondent about the man and the plot.(Photo: Colonel Domingo Monterrosa (R), speaking with one of his company commanders, 1983. Credit: Robert Nickelsberg/Getty Images)

28 Marras 201710min