The fourth-century Roman emperor Gratianus was an early visitor, followed much later by such luminaries as the Romantic poet Alphonse de Lamartine, Queen Victoria, Saint-Sa?«ns, and Rachmaninov.
Gratianus was a Roman empoeror.
For Louis XIV's wars against the Netherlands in the 17th century, the military architect Vauban built a line of fortifications at Calais, Dunkerque, Douai, Valenciennes, and ' still visible ' the great citadel at Lille.