Orthodox Christians in Israel, Bulgaria, Russia, Greece, Ethiopia and other countries around the world are celebrating Easter this weekend.

Carrying wooden crosses and singing hymns, pilgrims marked Good Friday by retracing the route that Jesus Christ took to his crucifixion. They walked in procession along the Via Dolorosa in the Old City of Jerusalem, to the Holy Sepulchre church, where they believe Jesus was buried before rising from the dead three days later.

Orthodox Easter
Orthodox Christian worshippers from Serbia hold crosses as they walk along Via Dolorosa during the Holy Week Good Friday procession in Jerusalem's Old CityBaz Ratner/Reuters
Orthodox Easter
Members of the Greek Orthodox clergy carry a cross along the Via DolorosaBaz Ratner/Reuters
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Pilgrims carrying wooden crosses enter the Holy Sepulchre Church during the Orthodox Good Friday processionThomas Coex/AFP
Orthodox Easter
Serbian Coptic Orthodox pilgrims carry wooden crosses as they walk along the Via DolorosaGali Tibbon/AFP
Orthodox Easter
A young Serbian Orthodox Christian pilgrim carries a wooden cross along the Via DolorosaGali Tibbon/AFP
Orthodox Easter
Christian Orthodox pilgrims carrying wooden crosses enter the Church of the Holy Sepulchre in Jerusalem's old cityGali Tibbon/AFP
Orthodox Easter
Ethiopian Orthodox Christians carry a wooden cross along the Via Dolorosa during the Good Friday procession in Jerusalem's old cityGali Tibbon/AFP
Orthodox Easter
Greek Orthodox Patriarch of Jerusalem Theophilos III and priests carry a large wooden cross in front of the Holy Sepulchre Church during the Orthodox Good Friday processionThomas Coex/AFP
Orthodox Easter
Orthodox Christian pilgrims place wooden crosses on top of a holy wall along the Via Dolorosa (Way of Suffering) in JerusalemThomas Coex/AFP
Orthodox Easter
A young boy yawns as he stands with Orthodox nuns along the Via Dolorosa during the Good Friday procession in Jerusalem's old cityThomas Coex/AFP

The date is taken from the old Julian calendar, which was introduced by Julius Caesar in 46BC as a reform of the Roman calendar.

It was replaced by the Gregorian calendar in the majority of Western Europe around 500 years ago.

Orthodox Easter
A worshipper passes under a table on which the Bible is placed, as a mark of respect to Jesus Christ, during a Good Friday mass at Alexander Nevski cathedral in Sofia. Bulgaria and other Eastern Orthodox countries celebrate Easter this weekendStoyan Nenov/Reuters
Orthodox Easter
Eastern Orthodox clergymen take part in a Good Friday mass at Alexander Nevski cathedral in Sofia, BulgariaStoyan Nenov/Reuters
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A woman prays in front of a wooden crucifix during the Good Friday service at the golden-domed Alexander Nevski Cathedral in Sofia, BulgariaNikolay Doychinov/AFP
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Greek Orthodox pilgrims light candles during the ceremony marking the Apokathelosis, the removal of Christ's dead body from the Cross, in a ceremony at the Church of the Dormition of the Virgin in Penteli, north AthensAris Messinis/AFP
Orthodox Easter
A Greek Orthodox monk looks at an image of Jesus crucified at the Church of the Dormition of the Virgin in Penteli, north AthensAris Messinis/AFP

On Maundy Thursday, Greek Orthodox Patriarch Theophilus III washed the feet of 12 of his clergymen at the Holy Sepulchre Church in Jerusalem's Old City.
The church was built by the Roman emperor Constantine and rebuilt by the Byzantine emperor Constantine Monomachus.

According to Christian tradition, Jesus washed the feet of his twelve disciples prior to the Last Supper before he was crucified. Christian churches worldwide commemorate this event as part of Easter Holy Week celebrations. The washing is usually done by the highest ranking clergyman.

Orthodox Easter
Greek Orthodox Patriarch of Jerusalem Theophilos III conducts the traditional washing of the feet ceremony during the Maundy Thursday procession at the Church of the Holy Sepulchre in Jerusalem's Old CityGali Tibbon/AFP
Orthodox Easter
Greek Orthodox Patriarch of Jerusalem Theophilos III exits the Church of the Holy Sepulchre in Jerusalem's Old City to begin the washing of the feet ceremony on Maundy ThursdayGali Tibbon/AFP
Orthodox Easter
Members of the Greek Orthodox clergy await the arrival of the Greek Orthodox Patriarch of Jerusalem Metropolitan Theophilos before the washing of the feet ceremony outside the Church of the Holy Sepulchre in Jerusalem's Old CityAmmar Awad/Reuters
Orthodox Easter
Greek Orthodox priests attend the washing of the feet ceremony at Jerusalem's Church of the Holy SepulchreGali Tibbon/AFP
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Armenian priests hold candles as they pray during the Maundy Thursday ceremony at St James Cathedral in Jerusalem's Old CityGali Tibbon/AFP
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Armenian Patriarch of Jerusalem Nurhan Menugian leads the traditional washing of the feet ceremony at St James Cathedral in Jerusalem's Old CityGali Tibbon/AFP
Orthodox Easter
A Christian pilgrim dips in the water at Qasr el-Yahud, where it is believed John the Baptist baptised Jesus, on the banks of the Jordan River, near the West Bank city of JerichoAmir Cohen/Reuters
Orthodox Easter
A Christian pilgrim dips in the water during his visit to the baptismal site known as Qasr el-Yahud on the banks of the Jordan River near the West Bank city of JerichoAmir Cohen/Reuters