BRIGHTON -- Cardinal Seán P. O’Malley will lead a group of pilgrims from the Archdiocese of Boston on a joint pilgrimage with the Greek Orthodox Christians of New England. The pilgrims will depart to Rome, Constantinople, and St. Petersburg on Sept. 16.

“The pilgrimage is part of the flourishing ecumenical relationship between the Catholic Church of Boston and the Greek Orthodox Church of Boston,” said Vito Nicastro of the archdiocese’s Office for Ecumenical and Interreligious Affairs.

“The goal is for us to pilgrimage together to these holy places so we are spiritually enriched and bound more closely by encountering the Triune God together,” he said.

The pilgrims will stay three days in Rome, three days in Istanbul (the former Constantinople), and an optional three days in St. Petersburg, Russia. Highlights of the trip are expected to include a general audience with the Holy Father, Great Vespers with the Patriarch of Constantinople and tours of the Vatican and Byzantine Mosaics of Rome; the Hagia Sophia Museum and Grand Bazaar in Istanbul; the Greek island of Halki. In Russia, visits are planned to the Hermitage Museum and the Orthodox churches of St. Petersburg.

Cost is $3,500 per person to Rome and Constantinople returning Sept. 23, plus $1,000 for those continuing on to St. Petersburg and returning Sept. 26.

Reservations for the trip are being accepted until Feb. 15. For further details or to join the pilgrimage contact Vito Nicastro at 617-435-0019.