Ideally—or perhaps unfortunately—situated at a major junction, Carcassonne was a stop on the east-west trade route linking the Atlantic to the Mediterranean, and the north-south trade route linking France and Spain. Thus, early on, the city was fortified, lest it be trampled or conquered. Romans were the first to fortify the site, followed by the Visigoths and the Franks (of Charlemagne fame).
Eight hundred years ago, in 1209, Carcassonne was the site of a siege where Roman Catholic crusaders expelled a group known as the Cathars, a religious sect that disagreed with central tenets of Roman Catholicism.
Today, take note that some elements of Carcassonne that are seemingly medieval, are actually not. The city had fallen into severe disrepair by the 1840s, and Eugène Viollet-le-Duc—a restoration specialist—took on the project of restoring it. The restoration carried on during much of the second half of the 1800s. Though Viollet-le-Duc’s work is deemed to have strayed from authenticity at times (for instance, the original didn’t have pointed cones topping the towers), his contribution is a work of art in itself.
Carcassonne is a stop on a number of tours offered by EF Educational Tours.