​The Glen is now a large estate, a mixture of farming enterprise and private residences, though it began life as a landscaped getaway for the aristocracy of the eighteenth century. The buildings were all constructed in the early nineteenth century, under the orders of the pioneering chemist (and discoverer of bleach powder) Charles Tennant. Most of the structures still in place at the Glen remain the property of the Tennant family, though the main attraction of the estate — Loch Eddy — wasn’t there during Charles Tennant’s time

Loch Eddy is an artificial construction, developed in the 1880s to make the estate more picturesque. In the years before the First World War, it helped to make The Glen attractive enough to draw such notable visitors as Prime Minister H.H. Asquith. It also gave rise to an influx of residents, as The Glen grew to have a population of about one hundred people and the facilities to support them: a schoolhouse, a post office, a village hall. Throughout the twentieth century, however, the population dwindled, and today The Glen is home to just a few dozen people, some of them only seasonal residents.

The Glen can be reached via a turn-off along the B709 through Traquair. The turn-off is signposted, just north of Traquair Kirk and not quite a mile south of Traquair House, past the turn-off to Cardrona. A narrow road will take you over the Quair Water, alongside the river and up to the Gate House. Visitors should park in the available area outside the Gate House and venture onto the estate on foot or on a bicycle. A range of paths will take you from the Gate House into the hills, across moorland, and around to Loch Eddy.