In 1853, Emperor Napoleon III commissioned the prefect of the Seine, Baron Haussmann, to modernise Paris. The old insalubrious centre was destroyed and replaced by thousands of buildings lined up along wide avenues that would solve the problems of traffic. Three new railway stations facilitated access to the capital. The creation of sewage and drinking water networks cleaned up the neighbourhoods, and the installation of urban gas lighting increased the safety of the inhabitants. Parks were designed (Montsouris, Buttes-Chaumont), and the Bois de Boulogne and Vincennes were developed. The Garnier opera house was built. The works employed 55,000 workers.