A police ring of steel surrounded Belfast city centre as a republican parade and associated loyalist protests on the main thoroughfare scared shoppers and visitors away and devastated trade.
Hundreds of police kept the two sides apart yesterday afternoon as they exchanged hate-filled insults on Royal Avenue.
Meanwhile in Londonderry, a huge event organised by the Apprentice Boys passed off with a "carnival-like" atmosphere and a police chief praised it as the most well-behaved parade he'd seen almost 30 years of policing.
The contrast between the two cities could not greater.
In Londonderry there is now an accepted accord on parading, while in Belfast there is still no agreement and the dispute over the 12th of July parade through Ardoyne is still rumbling on more than a year after it was halted.
The republican anti-internment parade yesterday snaked its way through nationalist areas of north Belfast after leaving Ardoyne on its way to Andersonstown in the west of the city via the main shopping precinct of Royal Avenue.
Missiles, fireworks and coins were thrown by a small number of people who took part in the loyalist protests against the parade.
Police said one of their officers and a member of the public were slightly injured.
The city centre was in a virtual lockdown with traffic excluded from several streets early in the afternoon and police water cannon on standby in back streets. The police deployment was one of the biggest ever seen in Belfast city centre with PSNI chiefs taking no chances following major trouble at the same parade last year when 56 officers were injured.
Shoppers and visitors unaware of the event were taken by surprise by the huge security operation and parade, while those who did know it was taking place stayed away in their droves.
Businesses complained that the massive disruption had hit their takings.
Glyn Roberts, chief executive of the Northern Ireland Independent Retail Traders' Association, said he witnessed "very ugly scenes" and said the business community will be urging political leaders to find agreement on controversial issues like parades.
Mr Roberts said: "There was significant disruption and particularly in the Royal Avenue area there is no doubt traders did lose a considerable amount of money. What type of signal does this disruption send out?"
Belfast Deputy Mayor Maire Hendron said: "It is frustrating that many businesses have lost a large amount of trade due to this parade and protest. This has been a largely peaceful parading season, but I hope that all sides will work together to minimise disruption in future years."
The Mourne Seafood Bar based at Bank Street near the parade route said their takings were "down £2,000" from the previous Sunday.
The Remedy Cafe Bar in the city centre also complained about losing trade as the police cordon blocked the street near their premises.