Ben Cruachan is the highest mountain in Argyll and sits atop the picturesque shores of Loch Awe. Passerbys are completely unaware that inside the mountain is a massive, fully functional renewable power station.

This hydro-powered station opened in 1965. It was the first reversible pumped storage hydro system of such magnitude in the entire world. The project took around six years to complete. The guided tours around the facility take visitors one kilometer deep inside the mountain. There they can learn about the construction process, and how the gigantic turbines utilize water from the nearby dam to generate electricity. The power station has another claim to fame as well, it was used as a setting for the James Bond film, The World Is Not Enough.