Secrets of Great British Castles

Dan Jones visits Lancaster Castle to explore its grisly history of crime and punishment, including the infamous Lancashire Witches trials and the martyrdom of the Jesuit priest Saint Edmund Arrowsmith.

Dan Jones explores the 900-year history of the beautiful Leeds Castle in Kent, from its origins as a royal Saxon family's manor and Norman stronghold to the private property of six medieval queens, a Tudor palace, a Jacobean country house, a Georgian mansion and an elegant 20th-century retreat for the rich and famous.

In medieval England, the North was ruled from York. Dan Jones explores the history of its castle, from the Viking Jorvik and the Normans, through the dark days of the anti-Jewish pogrom and the imprisonment of the Knights Templar, to one of its most colourful inmates - the legendary highwayman Dick Turpin.

Dan Jones explores the history of the Welsh capital's landmark, Cardiff Castle, and discovers more about the various incarnations over the centuries.

Edinburgh's handsome hilltop bastion is Scotland's most popular paid tourist attraction, but it also packs some formidable defences.