Dan goes behind the battlements of Dover Castle, where he descends into an underground lair to discover how a vast network of tunnels has been used to defend both the castle and the country for centuries.

Built by William the Conqueror, the Tower of London has been a military fortress, a palace, a royal mint, a prison, a zoo and a place of execution, a silent witness to some of the most momentous events in our history. Dan Jones reveals some of its secrets and tells the stories of the traitors, rebels and royalty who met their end inside its imposing walls.

Today Warwick Castle is a popular tourist attraction, but for centuries its walls echoed with the sounds of betrayal, bloodshed, murder and financial ruin. Dan Jones reveals the turbulent history which took place within the well-preserved walls of this imposing castle and the tales of the earls of Warwick who lived there.

Historian Dan Jones explores the turbulent history of one of Britain's most famous castles, Caernarfon. Dan is in the heart of Snowdonia exploring a stronghold built not only as an impenetrable fortress but also as a lavish royal palace fit for a fairytale - Caernarfon Castle.

Perched high on a volcanic crag overlooking the River Forth, Stirling has long been one of the most strategically important castles in Britain. Guarding the gateway to the Highlands, its battle-scarred walls have witnessed savagery and chivalry, intrigue, alchemy, adultery and murder. With the aid of location filming, aerial shots and dramatic reconstructions, Dan Jones examines the history of this stronghold and relates the stories of some of the powerful characters who have owned it over the centuries.

Dan Jones explores the history of Carrickfergus Castle in Co Antrim, one of the most ancient castles in Northern Ireland and a stronghold key to understanding the tempestuous relationship between Britain and Ireland. Dan travels to Rathlin island, where he reveals how hundreds of women and children were massacred in the name of Elizabeth I, and visits the tomb of former governor Arthur Chichester, who began a new colonization strategy using scorched earth tactics and laid waste to much of the land surrounding the town.

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

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

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 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.

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 visits the heart of the English countryside to explore Arundel Castle and the dramatic history of the Earls of Arundel.