A first-hand-guideline from Neil Dobson
Those who have tried a quick getaway at the end of the race know that the traffic at the end of the race can be a nightmare. I have a tried and tested a route for avoiding traffic, although it does involve watching the end of the race from Mulsanne. Before the end of the race (a good two hours before) you need to move your car up to Mulsanne. I would recommend parking in Mulsanne village somewhere (rather than the official Mulsanne enclosure car park) or at Hotel Arbor on the Mulsanne straight. Watch the end of the race from Mulsanne/Hotel Arbor and head back to your car. The map below shows Mulsanne corner at the bottom left (bordering the golf course) and in the top right hand corner the D304 joining the A28. This is the junction that you need to get to. Simply follow the escape route marked on the map!
From Mulsanne village take the Route de Mulsanne North. Route de Mulsanne runs off Avenue de Bonen and the turn to get onto it is between the roundabout and the Champion supermarket. Follow Route de Mulsanne towards the village of Ruadin (passing on your left the track that leads down to Hotel Arbor and the 2nd chicane). As you approach the village turn right at the first roundabout onto Rue du Vieil Hetre. This is the main road through the village. Follow for 0.5 Km and take the third turn on the right onto onto Route de Parigne-l’Eveque. This will take you out of the village. After 0.8 Km you will see a fork going off to your right. Ignore this and continue for another 0.2 Km and take a left turn onto Chemin de la Guiltiere. This road snakes its way through the fields for approx 2 Km until you arrive at a t-junction with the D304 (top right of the map below). Turn right and in approx 1 Km you will arrive at the roundabout where you can filter onto the N28 and happily whiz up to the A11 that will take you across the top of Le Mans, safely away from all the congestion. Hooray!
We encountered absolutely no traffic when leaving from Hotel Arbor in ’08. You might encounter a little bit of traffic in Mulsanne village itself but I very much doubt it. The whole East side of the circuit is deserted during the race when compared to the Western side of the circuit.
An alternative way of escaping the traffic is suggested by CA Member Ian Selvage:
If like me you like to watch the finish at the start/finish line and then join the crowds watching prize giving, you might find this a better route away at the end of the race. Getting out of the many campsites can be fraught with delays, especially when many multiple campsites feed into a single exit.
An alternative is to pack up and move your car out of the campsites, but instead of Mulsanne, I suggest moving it a couple of hours before the end to the Carrefour Hypermarket car park situated on Avenue Georges Durand . The supermarket is closed on Sundays; however the petrol station there is open as is the covered car park, where you can leave your car. (You could leave it beside the road if you are worried about car park clamping, but this, to my knowledge, is not a disease that has spread to Le Mans.)
The Carrefour is a couple of stops up from the circuit, but it's only a few hundred metres south to Tetre Rouge and an entrance to the circuit, so an easy walk. After the finish and prize giving, you can meander up over the Dunlop bridge and out of the circuit and back to your car, perhaps taking a coffee and slice of cake at the patisserie Bouvet Jean-Marie just before the Carrefour. Remembering that the main traffic delays are to the west of Le Mans, travel south and east.
I would suggest travelling south along Avenue Georges Durrand/D338 until the junction with the D323 ring road which you can take going east (unless like me you want a drive up the Mulsanne Straight on the D338 which should be open by then). Drive 8km along the A323 before taking the A28/A11 to Paris/Rouen/Nantes/Rennes/Tours and then join the A28/E502 still signposted Paris/Rouen…… After 5km take the A11 signposted Rouen/Caen/Alencon and away.