Train Director - Paris RERB Line
This line crosses Paris from the North-East to the South-West, with 2 branches at each of ends of the main line. It is used by approximately one million people a day!
In the southern suburbs, the two branches Robinson/Saint-Rémy are far from being equivalent. Indeed, the Robinson branch has only 3 stations, whereas there are 17 stations between Bourg-la-Reine and Saint-Rémy. In the North, the branches are roughly equivalent in distance but not in importance. The Charles de Gaulle Airport one is obviously more frequently served. The southern infrastructure was opened in 1846 between Denfert-Rochereau and Sceaux. The line joined Luxembourg thanks to a tunnel under Paris in the 1890s. At that time, steam traction trains imposed the construction of ventilation wells. Speed and frequency objectives were obviously different, which accounts for the numerous steep curves and narrow located stations in this part of the line. It was electrified with 1500V DC in the 1930s. In the 70s, the creation of a regional metro network was seriously considered, at last. This network would link cities of the whole Parisian area and cross the capital with few stations only so that this service would be faster than the urban underground. The recent Paris-Nord-CDG airport line is chosen. This implies to cross the Seine river and build a new tunnel heading to the Gare du Nord. The correspondence station Chatelet-Les Halles is reached in 1977 after very harsh slopes (up to 40‰) and a place under the river dedicated to a future station next to Notre-Dame. In 1981, the northern and southern parts are finally linked. Note that the first is not electrified in DC but in 25kV AC. Nowadays, RER B is one of the most crowded lines in Paris. Trains especially designed in 1980 are still used, showing how difficult it is to increase the performance of this 170 year old line.
The RER B serves important places for commuters as well as for tourists...
Exploitation in 2018
The service depends of course on the day time. From a general point of view, Robinson and Mitry-Claye branches are associated and Saint-Rémy/Massy-Palaiseau and Charles de Gaulle Airport are too. In general, trains are always omnibus in the North (except during off-peak time, some of them are direct between the Airport and Paris). In South of Paris, it's a bit more complicated since the 2 branches are very different. Please, also note that RER B trains have a 4-letter name. The first one shows the destination of the train and the second one indicates the service. The 2 last letters are not relevant and make the name pronunciable or funny.