Loch Mullardoch lies 8 miles to the West of the small village of Cannich, 30 miles or so South of Inverness, Scotland. Its Eastern end is surrounded by the private Mullardoch Estate and the former hunting lodge called Mullardoch House lies there. The Loch is 8 miles long and a little less than a mile wide at its broadest. It runs roughly East to West.

On the North shore lies the East Benula Forest and the mountain slopes of Sgurr na Lapaich and An Riabhachan. To the South are the peaks of Beinn Fhionnlaidh, Tom a Coinich and Toll Creagach. At the Eastern end is Mullardoch House and the road to Cannich, at the Western end is the West Benula Forest. The mountains that surround the Loch reach up to 4000 feet.

Montague Edwards styles himself 'Laird of Mullardoch' and he chose the Loch as the site to bring the city of Carcosa to Earth in December 1928, taking Alexander Roby there to aid him.

The Hastur Cult that had gathered around Lawrence Bacon, and Montague Edwards were told to meet in Inverness on December 5th. By December 10th, Carcosa had appeared spread around the Loch, although it could not be seen from a distance. Instead one found oneself already surrounded by the city without ever having knowingly entered it.

Carcosa left this world on the night of December 11th 1928, apparently taking the lives of a dozen people from the nearby village of Cannich. Now all is quiet once more at Loch Mullardoch.