In the west of Scotland, above the crystal-clear waters of Loch Awe, is Ben Cruachan, the soaring remnant of some distant geological upheaval. The pine-skirted mountain is the highest point of a horseshoe of scalloped granite, spewed boulders and scree faces, and helps cradle Cruachan Dam, a mighty reservoir that offers a glorious panorama of the maze-like lochs and hills that make up mainland Argyll.
This landscape, with waters that run downhill and Atlantic salmon that leap up, is home to pine marten and golden eagle, osprey and rutting red deer. Often, Cruachan – “conical hill” in Scots Gaelic and Argyll’s highest mountain – is also the backdrop for hillwalkers wearing fluorescent waterproofs or mosquito repellent and mountain bikers bearing broad grins.
But most visitors come here for what can’t be seen.
For Ben Cruachan is a hollow mountain – a shell of quarried rock – and 325m beneath the dam’s towering buttress hides one of the most monumental engineering projects in Europe.
Behind colossal walls of solid granite is Cruachan Power Station, a subterranean world of machine halls, transmission lines and turbines with a capacity of 440 megawatts – or enough to power nearly 100,000 homes. It took a workforce of 4,000 to scoop out the insides of the mountain in the early 1960s and, by 1965, they’d helped create the first hydroelectric power station of its kind in the world. An aerial shot of Cruachan reveals no hint of this underground triumph.