A 14th-century fortress built to protect the city gates, the Bastille became a prison under Cardinal Richelieu and was mobbed on 14 July 1789, igniting the French Revolution. At the center of the square is the 52m-high Colonne de Juillet, a green-bronze column topped by a gilded winged Liberty. Revolutionaries from the uprising of 1830 are buried beneath. Major public works vastly improved pedestrian and bike paths and link the square to the Bassin de l'Arsenal.