in the middle of the Snowdonia National Park. It's a busy mountain with walkers and of course a railway, so the most visible wildlife is restricted largely to those of the feathered variety ...

Despite their efforts, the Vincent Wildlife Trust and Snowdonia National Park haven't found any physical evidence (a body or photo) of pine martens in Wales since 1950. It's been nearly 10 years ...

Over four seasons, Iolo Williams goes to his favourite locations in Snowdonia to look for stunning wildlife, and meets people who help him discover the national park's true nature ...