Thousands of Palestinians and tourists are flocking to the West Bank city of Bethlehem to celebrate Christmas at the site where many believe Jesus Christ was born.
This year's celebration carries special significance for many Palestinians. Last month the United Nations granted Palestine status as a non-member observer state.
Earlier this year, Bethlehem's Church of the Nativity was recognised as a UNESCO world heritage site.
The designation also included part of a pilgrimage route, along which a Christmas procession headed by Latin Patriarch Fuad Twal will march later on Monday.
The parade will end in Manger Square, in front of the Church of the Nativity, which is built over the site where Christians believe Mary gave birth to Jesus in a cattle shed.
Later the patriarch will preside at midnight mass.
Scout troupes were already marching in the square to the rhythm of drums and bagpipes on Monday morning, watched by hundreds of tourists.
The mass is usually attended by officials from the Palestinian Authority including President Mahmud Abbas and Prime Minister Salam Fayyad.