(CNN) -- Pope Francis on Friday evening was leading a special Mass at St. Peter's Basilica in the Vatican to mark Good Friday, the most solemn day in the Christian calendar.
Later Friday, he will take part in a nighttime ceremony marking the Stations of the Cross, also known as the Way of the Cross or Via Crucis, at Rome's Colosseum -- one of the city's best known landmarks.
Roman Catholics worldwide will reflect Friday on the gospel account of the Lord's Passion, recalling the day Jesus died on the cross before rising three days later, according to Christian doctrine.
Holy Week, one of the most significant periods of the Roman Catholic year, will culminate on Easter Sunday with a Mass in St. Peter's Square, led by the pope.
On Holy Thursday, Pope Francis visited a home for the elderly and disabled, the Fondazione Don Carlo Gnocchi, to wash the feet of "12 disabled people of different ages, ethnicities and religious confessions," during a special Lord's Supper Mass, according to the Vatican.
It was the second time he has broken with Vatican tradition and washed the feet of ordinary people rather than priests.
Last year, only he washed the feet of two women and two Muslims at a juvenile detention center in Rome. Before this, modern Popes had only ever washed the feet of 12 priests at the Vatican, during the Mass for the Last Supper.
At his general audience Wednesday, Francis urged the faithful to see an example in Jesus.
"This week, as we follow Jesus along the way of the cross, may we imitate his loving obedience to the will of the Father, especially in times of difficulty and humiliation, and open our hearts to his gifts of reconciliation, redemption and new life," he said.
CNN's Delia Gallagher contributed to this report.