Pope Benedict XVI has made a historic visit to Istanbul's famous Blue Mosque on a third day of his stay in Turkey.
Inside the 17th century mosque, the pontiff prayed silently in what was seen as a gesture of reconciliation to the Muslims.
The Pope took off his shoes before entering the mosque. It marked only the second papal visit - after John Paul II's in 2001 - to a Muslim place of worship.
Security measures in Istanbul were said to be tighter than during US President George W Bush's visit to Turkey in 2004.
Earlier, Benedict visited the nearby Hagia Sophia which was built as a Christian church in the 6th century before becoming a mosque in 1453. It is now a museum.
The pope began the day by attending a service by Ecumenical Patriarch Bartholomew I, the spiritual leader of the world's 250m Orthodox Christians.
The original reason for the pontiff's visit to Turkey was to heal an old rift between the Western and the Eastern rites of Christianity.
But the visit was overshadowed by the Pope's recent comments on Islam which angered the Muslim world. Some 150 people protested against the pontiff's visit on Thursday.