Throngs of green-clad, shamrock-festooned revelers filled the streets of America’s most Irish big city on Sunday for the South Boston St. Patrick’s Day parade. Green, white and orange confetti -- the national colors of the Emerald Isle -- rained down along parts of the 3.5-mile (5.6-kilometer) route. Parade floats and marchers wound through the neighborhood of South Boston, a center of Irish-American heritage in a city where more than 1 in every 5 people are of Irish descent. Camryn Craddock was among those along the parade route, which included parts of Broadway, the neighborhood’s thoroughfare. “I just like the energy that everyone brings. Everyone’s really hyped up. It’s not boring," the Massachusetts resident said. "I didn’t even really see much of the parade, but just seeing everyone having fun was really nice and everything." Travis Wilshire, another reveler, agreed. “Last time I was here, I was just a little kid," the New Hampshire resident said. "So it’s definitely cool to see it, like, in a different age group, you know what I mean?” Spectators packed behind metal barricades playfully hissed as colonial reenactors wearing British tricorn hats and other period garb marched past on the warm but overcast day. The parade, which dates to the turn of the 20th century, marks both St. Patrick’s Day and Evacuation Day, which commemorates the day in 1776 when British troops left Boston after a protracted siege during the Revolutionary War. Parade-goer Alex Brough found people mostly behaved after violence and public intoxication marred last year 's festivities. Parade organizers moved up the start of the festivities and neighborhood leaders warned of " zero tolerance ” for rowdiness and shenanigans ahead of Sunday. Before the parade, transit police posted a photo on social media showing a pile of clear garbage bags filled with confiscated booze, including gallon-sized jugs filled with green liquid. “There is probably a lot of alcohol consumed today," the Bedford, Massachusetts, resident conceded. “We witnessed it, but I think still people were overall behaving rather well, considered.” The South Boston Allied War Veterans Council organizes the parade and this year’s chief marshal was retired Navy Lt. Cmdr. Alanna Devlin Ball, who grew up in the neighborhood and represented the U.S. at the 2023 Invictus Games in Germany where she took home gold in powerlifting. “Lt. Cdr. Devlin Ball’s 12 years career in the Navy serves as an inspiration to young women who seek to serve in today’s military. We are grateful for her service, sacrifice and power of example,” said U.S. Rep. Stephen Lynch, a South Boston native. The South Boston parade has been a source of political controversy in years past. The veterans council banned gay rights groups from marching in the parade up until a decade ago and a U.S. Supreme Court ruling upheld that right in the 1990s. Two gay and lesbian groups joined the parade in 2015. Organizers for one of the groups, Boston Pride, heralded the move as a point of progress at the time. Chicago held its St. Patrick's Day parade on Saturday. Philadelphia also celebrated on Sunday and New York City holds its parade Monday.