Bruce was certainly familiar with northern France, and in 1663 he made a further "foreign journey" at the behest of Lauderdale, although his itinerary is unknown. Whether by visit or through studying engravings, he knew several notable French houses including Vaux-le-Vicomte, Blérancourt, and the Chateau de Balleroy, the last the work of French architect François Mansart. These modern French designs, incorporating features then unknown in Scotland, such as the double-pile of major rooms in two enfilades, ranged back-to-back, were also influential on Bruce's designs.