Route nationale centre.
The point of the point
As written by Wanderstories, some 20 meters (66 feet) into the square from the cathedral’s central portal, there is a brass plaque in the paving stone. Produced in 1924, it marks the point from which all distances in France are measured from the exact center of Paris, here.
Some consider it as a place to make a wish, kiss, or dance. As in many cities, this is the place to stand if you wish to come back to Paris. :)
Mystery statue
Another great finding by Wanderstories is the mysterious statue that stood at this very spot until 18th century. No one knows when it first appeared in the square, but it dated from the pre-Roman period.
Point zero and Route nationale
A route nationale, or simply nationale, is a trunk road in France. Trunk roads in France are important roads which cross broad portions of the French territory, as opposed to secondary or communal roads who only serve local areas.
Their use is free, except when crossing certain structures subjected to toll. They are open to all vehicles, except on certain sections having the status of motorway (autoroute) and express road, both being reserved for motorized vehicles.
France has had 30,500 km of nationales and publicly owned motorways, but currently has 21,200 km of motorways and other nationales road, since 2007[1]. By comparison, routes départementales cover a total distance of 365,000 km. The main trunk road network reflects the centralizing tradition of France: the majority of them leave the gates of Paris. Indeed, trunk roads begin on the parvis of Notre-Dame of Paris at Kilomètre Zero. To ensure an effective road network, new roads that do not serve Paris have also been created.
The system dates back to December 16, 1811, when Napoleon designated a number of routes impériales (imperial highways). First class routes were numbered from 1 to 14; all began at Paris, radiating out in a clockwise manner. Route 1 ran from Paris north to Calais, and is still the general path of route nationale 1. Second class routes, from 15 to 27, did the same, while third class routes from 28 to 229 provided less major connections. During the Bourbon Restoration, in 1824, these routes were renamed routes royales (royal highways) and modified. Route 3, Paris to Hamburg via Soissons, Reims and Liège, was renumbered to 31 and 51, and the subsequent routes were shifted down by one. Routes 19 and 20 were completely outside the post-Napoleon France, and so 21 to 27 became 18 to 24. In 1830 the highways were renamed routes nationales.[2]
In the 21st century, the French Government has downgraded many the routes nationales, such as RN7 from Paris to the Côte d'Azur to departmental status.[3]