ROCHE-SUR-YON, LA, a town of France, the chief town of the department of La Vendee, lies 278 miles south-west of Paris by the railway to Sables d'Olonne, on an eminence 164 feet above the sea on the right bank of the Yon, a little tributary of the Lay, itself an affluent of the Pertuis Breton. In 1881 the population of the town was 9965, of the commune 10,634. The castle of La, Roche-sur-Yon, which probably existed before the time of the crusades, and which was frequently attacked or taken in the Hundred Years' War and in the wars of religion, was finally dismantled under Louis XIII. ; and when Napoleon in 1805 made this place the chief town of a department the stones from its ruins were employed in the erection of the administrative buildings, which, being all produced at once after a regular plan, have a monotonous effect. The equestrian statue of Napoleon I. in an immense square over-looking the rest of the town ; the statue of General Travot, who was engaged in the " pacification " of La Vendee ; the museum, with several paintings by P. Baudry, a living native artist of note, are the only objects of interest. The dog fairs of Roche-sur-Yon are important. Napoleon-Vendee and Bourbon-Vendee, the names borne by the town according to the dominance of either dynasty, gave place to the original unpolitical name after the revolution of 1870.