The route was specifically designed to connect the coastal portion of Stonehaven to a crossing of the River Dee at the southern edge of Aberdeen. Stonehaven was most noted in the Middle Ages for the fortress of Dunnottar Castle, controlling land and sea movements of military might from its rugged promontory jutting into the North Sea. This fortress along with Cowie Castle at the north of Stonehaven effectively controlled all coastal land and sea movements to the north. Proceeding north from Cowie Castle, the Causey Mounth crosses the Burn of Muchalls at the Bridge of Muchalls and thence proceeds northward past Muchalls Castle. The trackway passes the ruins of the Episcopal Chapels, dating to 1624 situated on lands of the Muchalls Castle Estate, and thence northerly beside the present day Saint Ternan's Church, which is the successor facility to the ruined chapels.