Hassan Tower is a historic minaret of an incomplete mosque located in the heart of the Moroccan city of Rabat. The minaret was built during the reign of Almohad Caliph Abu Yusuf Yaqub al-Mansur in the 12th century AD during the construction of the Hassan Mosque, which was considered one of the largest mosques in that period. But this construction stopped after the death of the Sultan in 1199. The minaret was damaged by an earthquake in 1755 and was completely restored in the 1960s. Hassan Tower was inscribed as a UNESCO World Heritage Site in 2012 as part of Rabat, Modern Capital and Historic City a Shared Heritage.