Within the Palais des Evénements, this plenary is dedicated to major congresses and conventions. One half of the hall is equipped with a retractable seating system to accommodates events from 1600 to 3200 people. The other half of the available surface leaves the possibility to use it as reception, exhibition, or catering of the event.

The flexibility of this hall is created by an acoustical separation wall, removable retractable seating platforms and stackable seats. Because constricted heigh the system was conceived with double platforms to gain seating space. The rectable seating system is equipped with 1560 Flex seats. Extra seating capacity can be created by an additional 52 rollable seats of the same design and 1650 stackable loose seats with removable armrests.