King Hassan Mosque Casablanca MoroccoKing Hassan Mosque in Casablanca Morocco. The Hassan II Mosque in Casablanca was completed in 1993 after great expense and artistic labor, and the result is that it is the 3rd largest mosque in the world. Its gleaming newness and tremendous wealth is a stark contrast against the rest of Casablanca. It's a vast building that can hold 25000 worshippers and accommodate a further 80000 in the courtyards and squares around it. The mosque was designed by the French architect Michel Pinseau and is topped by a soaring 210m-tall minaret, which shines a laser beam towards Mecca by night. In addition to this high-tech call to prayer, the mosque also has a centrally heated floor, electric doors, a retractable roof and a section of glass flooring allowing the faithful to see the Atlantic washing the rocks below.