Haussmann created expansive gardens (Montsouris, Luxembourg), a network of broad avenues, and renovated Place de l'Etoile, Place Léon-Blum, Place de la République, Place de l'Alma, the Arc de Triomphe, and the Grand Opera House (1861-1875), as well as undertaked important water works, city facilities and public monuments. Also, Haussmann had the Gare de Lyon constructed in 1855, the Gare du Nord in 1865 and the construction of 600 kilometers of aqueduct (1878).
On the map of Paris it's easy to identify Haussmann's work. All those straight, wide streets, the Grands Boulevards – Boulevard St Michel, Boulevard de Montparnasse, Boulevard Haussmann – that slice across an older plan remind us that he was the architect of modern Paris. 
Additionally, Haussmann improved rail transportation, a better lighting and water sanitation.
Paris emerged from being a mediaeval city to become a modern capital. Paris in 1853 was a morass of narrow, twisting medieval passageways, so it was remarkable how much of Haussmann's dream was accomplished in the next fifteen years, creating the Paris we know today. It was the biggest transformation in the history of Paris.