The spiritual leader of the world's Orthodox Christians is set to visit Louisiana, New York, Georgia, Maryland and Washington, D.C., during a trip to the United States.

Ecumenical Patriarch Bartholomew I arrived in New Orleans on Tuesday to preside over the eighth Religion, Science and the Environment Symposium. Next week, he will celebrate the 10th anniversary of the enthronement of Archbishop Demetrios of America in New York.

Bartholomew is also expected at an Ecumenical Gathering of Peace at the Annunciation Cathedral in Atlanta next week.

The patriarch will mark his 18th year in his role as ecumenical patriarch in a service at Sts. Constantine and Helen Church in Annapolis, Md., on Nov. 2.

In Washington, the patriarch is scheduled to meet with Vice President Joe Biden and Secretary of State Hillary Clinton.