The project consists of a Mosque situated Square of Yser in Liège which can welcome up to 900 persons. Except the room of prayer the program contains classrooms, library, multi-purpose hall, accommodations provided with the job and a small day-nursery. The place who's a triangle and the direction of Mecca manage the orientation and the setting-up of the building. Three big monoliths support a big parallépipède who's made of a double-skin. The opposition between the heaviness of the concrete and the lightness of the moucharabieh stresses the effect of floating. A split allows to create a central yard bringing some natural light. We have the vastest functions as the prayer or the multi-purpose hall there. The main tour contains the religious functions and the main circulation, the others contain the secondary functions, worth knowing the day-nursery, the library, the administration and the accommodations provided with the job.