Along the way, Michael investigates the Highland Boundary Fault, which separates the Highlands from the Lowlands, and learns how Scotland’s geology has influenced its history.

Between Loch Lomond and Loch Long, Michael explores the deep waters of Garelochhead at Faslane, where Britain’s nuclear-armed submarines are based.

Alighting next at the pretty Falls of Cruachan station, Michael ventures inside the hollow mountain of Ben Cruachan to visit a power station with a reservoir on top of it. Electricity is generated here using an ingenious method known as pumped storage. Michael meets one of the ‘tunnel tigers’ who dug out the mountain in the early 1960s.

At Connel Bridge, Michael joins a marine biologist on an RIB to collect phytoplankton from Loch Etive as part of a long-term project to monitor the health of the waters.

On TV

Saturday16:30 or BBC i player