Lots going on in St Patrick's Day in Charleston, Mass is 8am at St Patrick's Church downtown. Be sure to take a look at the gravestones adjacent to the church, lots of Irish buried there from the 19th.
The parade begins at the church following Mass. At noon the Irish flag is raised about city hall and there's a ceremony for that.
While in the area stop by the Irish Memorial Park on Charlotte Street.
Then go celebrate in one of the Irish owned pubs in the area
McCanns in Mt Pleasant & Seabrook
Seanachai on Johns Island
St James Gate on Folly
Madra Rua in Park Circle.