Series exploring the hidden corners of the UK. In the Brecon Beacons, Adam Henson tries to master fly-fishing and Ellie Harrison visits Britain's deepest cave.

Series exploring the hidden corners of the UK. In North Yorkshire, Adam Henson discovers the remains of a forgotten glass-making industry.

Series exploring the hidden corners of the UK. In Scotland, Ellie Harrison probes a monster mystery at the heart of Britain's deepest water.

Matt Baker and Julia Bradbury embark on an epic adventure to unlock the astonishing beauty of Secret Britain. They start in the far South West of England, and the first leg of their journey takes them all the way to Dover across some of the most crowded parts of the UK. Yet even here there are hidden corners and forgotten stories. Matt explores Britain's only desert, while Julia goes off the beaten track to discover the shady green world of Dorset's holloways.

Matt Baker and Julia Bradbury explore the hidden heart of the UK on the second leg of their journey across Secret Britain. It is a journey of revelation, that takes them from the eerie flatlands of East Anglia to the staggering sea cliffs of Pembrokeshire. Matt searches for a mysterious island in the enigmatic waterworld of the Norfolk Broads, while Julia discovers a secret side to Swindon.

Matt Baker and Julia Bradbury are on the road north on the third leg of their epic adventure to unlock Secret Britain. Even here, in the best loved areas of the Peaks and Lakes, there are still hidden corners of the countryside just waiting to be discovered. Julia takes a trip into the stunning underground limestone world beneath Yorkshire, while Matt relives childhood memories as he explores a secret ancient woodland on the Durham coast.

On the final leg of their epic journey across Secret Britain, Matt Baker and Julia Bradbury head for the borderlands and beyond to discover that there is much more to this wild landscape than meets the eye. Intrepid Victorians, Roman Emperors and imaginative locals have all left their mark; their secret stories all hidden in this astonishing landscape. Matt takes the train to Britain's most remote railway station while Julia explores Glencoe in search of a hidden valley that lives up to its name.