In tonight's episode:
Nicola Hendy prepares herself for an adrenaline-filled ride as she rides the longest and fastest zip line in Europe.
With the potential to reach speeds of up to 100 mph, it's easy to see why people are attracted to the zip line, which is built high above Penrhyn Quarry.
But while screams of delight now reverberate around the quarry, it hasn't always been a place for fun and games. In 1896, Penrhyn Quarry saw the longest industrial dispute in British history, with workers demanding better pay, and safer conditions.
The quarry owners, desperate to end the strike, offered them large financial incentives.
Dr Dafydd Roberts from the National Slate Museum explains: