Many thanks to you Rollo75 for your comments.
I did indeed make a mistake by simplifying the routes taken by the « Circuit des 24 heures ». The roads closed to road traffic are more numerous.
So we have :
1 - permanent road: it starts at the Chicane du Raccordement and ends at the Virage de la Chapelle. It is permanent throughout the season since it is part of the Bugatti circuit which hosts other car and motorcycle events;
2 - road open to road traffic outside the 24 Hours of Le Mans. This concerns the circuit from the Virage de la Chapelle to the first of the Porsche curves;
3 - portions of roads closed to road traffic and unused outside the
24 Hours of Le Mans. (I am not able to list them all with certainty). But this is the case with the Porsche curves, "this rapid sequence begins where the track leaves the departmental road to reach a section which is closed all year round since it is not part of the Bugatti circuit, like the straight line from Maison Blanche that follows. In fact, this whole part, from the first Porsche curve to the Ford chicane is often called
new portion in French.
The name Virages Porsche (Porsche curves in English) is in fact erroneous. Purists will talk about Virage Porsche, Virage du Pont and Virage du Karting. This whole part was refitted in 1972 thanks to a large-scale renovation plan ranging from the Virage d'Arnage to the stands. » (1) In other words,the only permanent track is the Bugatti circuit;
The Hunaudières straight takes the road to Tours. This straight line is cut by two chicanes “initially called the
Nissan chicane for the first and
Carte S for the second, they have adopted different names over time, to highlight partners. (...) If you want to be precise, talk about the Arche bend for the first chicane, then the Florandière bend for the second. Or else, keep saying "the two chicanes". » (2)
I'm not sure, but it may be that the two chicanes - which leave the route de Tour - are closed to traffic outside the 24-hour event.
One thing I am certain of is that the Targa Florio - a famous Italian race for sports-protos and GTs - used to take place on 72 km (45 mi) of Sicilian roads... completely closed during the event !
Enjoy!
(1)
https://www.24h-lemans.com/fr/actua...es-du-grand-circuit-les-virages-porsche-20148
(2)
https://endurancemag.fr/les-hunaudieres
relievedface:
https://en.wikipedia.org/wiki/Targa_Florio