"Searching for the Grand Paris" "How did transportation evolve in and around Paris?" -The issue of mobility at a metropolitan level, to use the current term, really appears as the industrial city emerges during the 19th century and as it becomes demanding in terms of population movements, especially to commute, as of the mid-19th century. This coincided with major reconfigurations of urban spaces during the Second Empire and Haussmannian times. Within many conversations regarding flows, people's surface travels were a subject for reflection. The aim was to accelerate travels, make them more fluid, to bring people to their workplace by modifying their access. Haussmannian policies, which focused on networks, redesigned the city around new arteries and fast-evolving transportation systems, the ancestors of contemporary public transportation. The Parisian métro becomes a symbol of a prominent issue of French society: tardiness. In Paris, in the early 20th century, in 1900, when the métro was launched, we felt that we had caught up with other metropolises, such as London, Berlin, Budapest or New York, which had adopted efficient massive underground transportation systems long before us. Paris was lagging behind but the city adopted more innovative technical solutions, such as electricity. And it compensated for its late start. Because of its urban structure encircled within 20 arrondissements, Paris created a more tight-knit network with stations which were much closer than in the London or Berlin undergrounds. When the métro was born, it served an industrial city which had taken a century to grow, and it helped expand it. First, the métro was still confined to the 20 arrondissements, as it was built by the city and validated by the city council, so they were not trying to expand further beyond the gates, which still existed as part of the city walls. They would only fall into disuse after World War I. In other words, the métro would shape the city, as an industrial city which it completed. Thanks to the métro, commuting became possible, in other words travelling to and from work, which played an important part in population flows. Soon enough, the métro would predate bus networks. It stood for modernity when surface transportation was somewhat archaic. The first Parisian tram, which was created in the 1820s, was technologically outdated on the brink of World War I. As for omnibuses, they were no longer suitable as they were horse-drawn. They were only just starting to use engines after the 1906 Paris Motor Show. In 1913, there no longer were any horse-drawn omnibuses on the surface network. So the regularity of the métro was a major modern innovation, and helped make it possible to cover all 20 arrondissements in the capital. At first, the métro was integrated into Paris, so it did not connect to the suburbs. The first extensions only came during the interwar period and they were hard to implement. A few elected officials asked for an extension of the network, for what could almost be considered as the first express regional network, such as Henri Sellier and people who, ahead of their time, defended an administrative Grand Paris, which would fail because of the economic crisis of the 1930s. At first, the métro solidified Paris's image, that of a modernized city. Why? Because the network covering the entire inner city was as regular as it could be. They tried to create a fair network that could allow for quick travel based on where people lived and that would not isolate anybody from a fast mode of transportation. Another important issue regarding the métro and beyond the lines, was its image. There was the street furniture associated with the métro, made by Guimard, which gave the city a new kind of urbanity. It was the first time, since Haussmann and his project managers and urban planners, that a mode of transportation changed the city's image. The routes were also important, of course, to the south, to the north, to cross from east to west, and they tried to cover the entire city as much as possible by capillarity. So, more than a mode of transportation, more than a choice of mobility, the first métro played a real part in urban planning. RER also helped the city catch up. The network did not change for about 50 years. The Société des transports en commun de la région parisienne was criticized, before it became the RATP in 1948. Its goal then became to guarantee a public transportation service. RER was the result of a crisis and of the maturation of an idea born in the 1920s, that of the extension of the network to the suburbs. This extension was first covered by the tram network, which had technological limits and was in some ways outdated. This is why it disappeared in the 1930s both in Paris and in the suburbs. With the development of the RER, a different vision of the region, which would later be Ile-de-France, emerged with it. So the division into departments in 1964 accelerated the dynamics to cover a much wider territory, that had to be provided with express and regional transportation. From this standpoint, RER would reproduce older patterns, such as interconnection through the city center, which was complicated to implement. So in some regards, it was a deconcentration, with new town policies, including the RER, new, faster travel speeds, while also a concentration as the network continued the pattern of centralization in Paris.