In this first episode, Will begins his tour around Wales in the north of the country. From the biggest abandoned slate mine in the world to a forgotten mansion concealed in a wood, and from a decommissioned nuclear power station to a Victorian invention lying at the bottom of the sea, Will uncovers historical gems in parts of north of Wales you never knew existed. It could also be your last chance to see some of the Welsh history that is vanishing right in front of us.