The prime shopping district at Royal Avenue reverberated to a wall of sound – sectarian jeers and taunts from both loyalists and republicans as startled shoppers and surprised tourists looked on.
It took 15 minutes for a republican anti-internment parade to pass through the city centre as plastic bottles, coins and marbles were hurled at the marchers by loyalist protesters.
Earlier, hundreds of people gathered in the shadow of republican murals in Ardoyne to start the march off which then went through the north of the city, their numbers swelling along the way with groups joining in at the New Lodge and also at Donegall Street.
It could have been a lot worse – like last year when dozens of police were injured when the parade was rerouted away from Royal Avenue by the organisers when trouble erupted.
Republicans were holding the anti-internment parade through the city centre from Ardoyne in the north of the city along Royal Avenue, up Castle Street and on to the Falls Road.
Loyalists filed counter-protests and one was hemmed in on Royal Avenue courtesy of a huge police operation.
As an estimated 1,000 republican marchers and bands approached the loyalist crowd of several hundred, a cacophany of boos and jeers and a tirade of taunts were exchanged.
Then came a few plastic bottles followed by banger fireworks which blasted on the road in the middle of the marchers.
Marbles were thrown and umbrellas also hurled like spears from the loyalists, and occasionally the marchers threw some of the objects back.
At the bottom of the Falls Road, a Belfast tourist sightseeing bus waited as the parade passed by and staff member gave a commentary telling the goggle-eyed tourists they were witnessing "living history".
A cruise ship was also in town but it is understood tourist chiefs persuaded most passengers to go to the Odyssey rather than witness any rowdy scenes.
One police source said: "With loyalists and republicans cheek by jowl it was inevitable there was going to be some aggro – but at least there was no widespread violence."