Huw Edwards and the history detectives discover a lost church (Tal-y-Cafn), search for the oldest castle (Hay-on-Wye) gate in Europe and find out how the great engineer Thomas Telford built the highest aqueduct (Pont Cysyllte) in the UK.

Huw Edwards and his team decipher the writing on a stone pillar (Eliseg's Pillar), recreate what an iron age fort (Gaer-Fawr) would have looked like and uncover an 18th century copper works (Swansea).

This time, Huw Edwards and his team examine a Tudor house (Old Impton Farm), a Roman theatre (Tomen-y-Mur) and a chapel (Llanelli).

Huw Edwards and his team interpret the strange humps and bumps in the Welsh uplands (Pen-blaen-Milo). A model farm (Leighton Park Farm) and a medieval wall painting (Ciliau).

Huw Edwards investigates the case of the disappearing house near Llandeilo. WWII defences at Holyhead and searches for a lost castle at Portmeirion.

Huw Edwards narrates a look at Stonehenge's link to the Preseli Hills, Swansea's medieval beginnings and bomb-damaged streets, plus the secrets of the highest house (Gwylfa Hiraethog) in Wales.

A look at how laser scanning helped uncover the history of Vivian quarry in North Wales, the rediscovery of a medieval fish trap in Fishguard harbour and a visit to architect Herbert North's contribution to Llanfairfechan.

Discovering what may be a Roman villa near Trawsgoed in Mid Wales, uncovering the hidden secrets of a Renaissance ceiling at St David's Cathedral, and observing the preservation of a major sculpture at College Harlech.

A look at the house that time forgot near Raglan, and a visit to the World War I training trenches at Penally in Pembrokeshire. A look at the 18th century's largest copper mine (Parys Mountain).

A look at the legacy of a Tudor lord who wanted to turn Denbigh into the capital of North Wales. Pembrokeshire's Iron Age Forts. Strata Florida sheep farm.

Eddie Butler and Heledd Fychan find out if the Gwent Levels flood of 1607 was a tsunami. Disappearing rural cottages, and is the chain bridge at Llangollen is the oldest of its kind in the world.

Eddie learns to play handball at Nelson's unique handball court - the only one in the UK. Does the Norman town of Grosmont have the oldest church roof in Wales? How Bardsey Island changed through the ages. Updating traditional rural cottages.

The remarkable story of a 19th-century cursing well near Abergele, the secrets of a showcase mine (Ystrad Einion). Visiting Brynmawr Welfare Park to discover how it was built by volunteers from Europe. Pre-historic rock art on Anglesey as it's never been seen before,

A look at the decommissioning of the Trawsfynydd nuclear power station, the lost settlements of Skomer Island and the search for the wreck of a Bristol Channel pilot cutter.