The Amphi. Bloch is at the groung floor of building 772 inside the L'Orme des Merisiers campus of the CEA Saclay research center. It is within the same building as the IPhT and the Service de Physique de l'Etat Condensé (SPEC).
(NOTE that L'Orme des merisiers is outside the main CEA center (see picture)
The CEA-Saclay research is located on the Saclay plateau, approximatively 20 km in the South-West of Paris.
Determine the best route with mappy or via Michelin. As arrival point, fill in Route de l'Orme, town Saint-Aubin, zip code 91190. Enter l'Orme des Merisiers. Ipht-SPEC building is located right of the road.
To know the optimal way depending on your departure place and time, take a look at the website of the local public transports. Concerning the arrival point, select "Arrêt, gare" and then fill in the fields with "Orme des Merisiers", commune "Saint-Aubin".
From Paris or from the airports, take the B-line of the RER, direction Saint-Rémy-les-Chevreuse (from Orly, take first the Orlyval until Antony).
Take off the train at Le Guichet (roughly 35 minutes from Paris, 1h15 from Charles de Gaulle airport).
At the train station Le Guichet, take the tunnel to go on the other platform, then leave the station and go on your left twice,then on your right, to reach the bus station. There are free CEA bus that are waiting on the left side of the street, and that leave at 7h55, 8h25, 8h50, 9h00, 9h25, 9h40 and 12h55. They reach the Orme des Merisiers campus in 10 minutes. Otherwise, take the local bus 269.002 until the Orme des Merisiers campus. (15 minutes). You can find the schedules for thesebus here.
WARNING : Ask the driver to make a stop at the Orme des Merisiers ! Do NOT go to the main campus of the CEA.
The main entrance of the Orme des Merisiers in located on the D128 road, at 400m of the Saint-Aubin roundabout between the N306 and D128 roads.
Once you have entered the Orme des merisiers, go straight for approximately 8 minutes and turn on your right when you can ; the SPEC-IPhT is the only building 772/774. Acros the main entrance by the main parking, the Amphi. Bloch entrance is within the main hall. IPhT entrance if in front across the main hall and SPEC entrance is on your right (Secretary: building 772, first floor, room 133).