Centuries of British political history has played out across Whitehall, with key decisions taken in the many government buildings that line the streets around the Palace of Westminster. But what secrets are contained within their walls and behind their doors? How have the buildings changed over the years? And what secret tunnels lie beneath the basements of Whitehall?
 
Special guest Gus O'Donnell joins the IfG’s Cath Haddon and Alex Thomas to reveal the secret map of Whitehall.
 
Presented by Hannah White
 
Produced by Candice McKenzie