The volunteers who are mapping the world's unmapped places and people
BBC World Service
2/6 Josie Long presents a sequence of short documentaries about acts of trespass.
BBC Radio 4
The impact of technology and psychology on early 20th-century friendship.
1/2 The Gulf state of Oman grants faiths other than Islam a surprising amount of freedom.
Jolyon Jenkins speaks to the unsung enthusiasts on a mission to protect us from asteroids.
Keith Joseph's impact as the trailblazer for Thatcherism is assessed by James Landale.
Dr Thomas Dixon explores how the international friendship movement flourished after WWI.
1/4 The show must go on - as pub singer Pat Mallon prepares for major surgery. With Alan Dein.
Can science stop sharks attacking humans?
How Senegalese captain Mbaye Diagne saved hundreds of lives during the Rwandan genocide