Stock Photo - Hassan Tower or Tour Hassan is the minaret of an incomplete mosque in Rabat, Morocco. Commissioned by Abu Yusuf Yaqub al-Mansur, the third Caliph of the Almohad Caliphate in 1195, the tower was intended to be the largest minaret in the world along with the mosque, also intended to be the world´s largest. When al-Mansur died in 1199, construction on the mosque stopped. The tower reached 44 m (140 ft), about half of its intended 86 m (260 ft) height. The rest of the mosque was also left incomplete, with only the beginnings of several walls and 348 columns being constructed. The tower, made of red sandstone, along with the remains of the mosque and the modern Mausoleum of Mohammed V, forms an important historical and tourist complex in Rabat. Photo: André Maslennikov.