Acknowledging Casablanca's lack of historical monuments, King Hassan II stated (on his birthday in 1980) his desire for the city to "be endowed with a large, fine building of which it can be proud until the end of time." Thirteen years later, he inaugurated the Hassan II Mosque. Built on a rocky outcrop of reclaimed land -- in response to Hassan II's translation of the Koranic verse that proclaims God's throne was built upon water -- the mosque is a truly marvelous piece of architecture. Designed by French architect Michel Pinseau, it can accommodate 25,000 worshipers inside and 80,000 more outside. At the time it cost more than $750 million, all of it paid by public money. It took 6 years and more than 6,000 craftsmen to build. They used marble from Agadir, cedar wood from the Middle Atlas, and granite from Tafraoute; Venetian glass was the only imported material. The mosque's most exquisite examples of Moroccan craftsmanship are the blankets of zellij, some designs more than 10m (33 ft.) high. The mosque is not only one of the world's largest, it's also one of the world's most high-tech, with heated flooring, a retractable roof, a section of clear-glass flooring -- for worshipers to see God's water below -- and even a laser light atop its 210m-high (690-ft.) minaret, pointing the way to Mecca each night. There's also an ablutions hall with more than 40 fountains and two public hammams.
To see the mosque's interior, you have to take a guided 1-hour tour, which I highly recommend. It's only from within the vast prayer hall that you can appreciate the enormity and grandness of its scale. Visitors must be dressed respectfully (shoulders covered and preferably long trousers or skirt), and shoes are removed once you step inside. The mosque is located about a 10-minute petit taxi ride (around 15dh) from the city center.