OLD ST. MARY'S Church in Society Hill, Philadelphia's first Catholic cathedral, will celebrate its 250th anniversary Sunday in conjunction with Memorial Day weekend.

A commemorative Mass and parade will take place at the church, on 4th Street near Locust.

Old St. Mary's, founded in 1763, was the second Catholic church in the city. It served as the first cathedral for the Diocese of Philadelphia, from 1810 to 1838, and also has significant connections to the American Revolution.

George Washington, John Adams and other members of the Continental Congress who signed the Declaration of Independence are among the Founding Fathers who attended services at Old St. Mary's.

Old St. Mary's current pastor, the Rev. Paul DiGirolamo, said the church is holding the celebration on Memorial Day weekend so that Archbishop Charles Chaput can attend after recovering from knee surgery, and to honor those who died in the Revolutionary War, many of whom are buried in the church's cemetery.

DiGirolamo and Chaput will place a wreath on the grave of Commodore John Barry, a former Old St. Mary's parishioner who fought in the Revolutionary War and is often called the "Father of the American Navy."

The church's significance goes beyond the Founding Fathers to the waves of Irish and German immigrants who attended the church in the 19th and early 20th centuries, DiGirolamo said.

"It's a reminder of the past and where we all come from in the United States," he said.

DiGirolamo, 55, a South Philly native, said he remembers stopping by the historic church after shopping trips in Center City as a boy.

Today, with a congregation of mostly Society Hill residents, DiGirolamo said, the church mimics the neighborhood. About half the congregants are homeowners and half are new renters, he said.

The celebration begins with 11 a.m. Mass on Sunday.

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