04 Jun 2009, Cairo, Egypt — epa01750812 US President Barack Obama (R) and US Secretary of State Hillary Clinton (C) listen to the guide tour (L) as they visit the Sultan Hassan Mosque, before giving his speech from Cairo University, during his visit to Cairo, Egypt on 04 June 2009. Obama is attempting to open a dialogue with the Muslim world by visiting Saudi Arabia and delivering a major speech in Cairo. The Sultan Hassan Mosque is considered stylistically the most compact and unified of all Cairo monuments. It is one of the masterpieces of Mamluk architecture. EPA/SAMEH REFAAT POOL — Image by © SAMEH REFAAT POOL/epa/Corbis