More than 500,000 Dubliners and visitors cheered the Irish capital's St. Patrick's Day parade Friday, a massive event featuring face-painted troupes of children, American high school bands — and a major security effort to deter drunken violence afterward.

About 1,000 police were deployed to try to prevent alcohol-fueled trouble after the parade finished its two-mile route down the city's major boulevard, O'Connell Street, and across the River Liffey to St. Patrick's Cathedral. A police commander monitored street conditions from a central bank of closed-circuit surveillance cameras.

But spectators and marchers alike said their main concern was braving a bitterly cold March day. And as darkness fell, the drunken mayhem Dublin suffered last year failed to materialize again, partly because of the exceptionally chilly weather.

The Garda Siochana, Ireland's national police force, said its officers were making dozens of arrests Friday night for drunken and disorderly behavior, but stressed it was no more than on a typical weekend in Dublin.

Meanwhile, in Belfast, capital of Northern Ireland, a St. Patrick's Day parade and concert billed as "Snake, Rattle 'n' Roll" also passed off without sectarian trouble.

Reflecting the tension between British Protestants and Irish Catholics, Belfast did not even have a St. Patrick's Day parade until 1998 because of Protestant hostility toward the display of Irish national symbols.

For the first time, Belfast City Council sponsored and helped organize Friday's celebrations, which had previously been run by Catholic hard-liners.

A key condition of the Belfast council's support was a ban on marchers' waving Irish flags. Instead, shamrock flags designed to be neutral were handed out to the mostly Catholic crowd, some of whom bought Irish flags from a street vendor instead.

The Police Service of Northern Ireland reported three arrests for drunken and disorderly behavior, but no sectarian trouble. It credited the wintry weather for discouraging drinking or confrontations in the streets.

By contrast, St. Patrick's Day last year coincided with exceptionally balmy weather. Police in Ireland arrested 714 people, including 252 in Dublin, in drunken brawls and other violence. It was the worst street trouble on St. Patrick's Day in living memory and opened a national debate on alcohol abuse, particularly among teenagers.

Dublin's liquor stores mostly stayed closed until late afternoon Friday to deter people from showing up drunk at the parade. The government also broadcast ads warning adults not to buy alcoholic drinks for teens.