BELFAST, Northern Ireland — Thousands of Protestants marched peacefully through the heart of Northern Ireland's capital Saturday amid a heavy security presence.

It was one of Belfast's biggest parades in years, and police were deployed in large numbers to prevent street clashes between marchers and Northern Ireland's Catholic minority.

Members of the various Protestant "loyal orders," so-called because they're loyal to Great Britain, trooped down Belfast's streets festooned with buttons, tassels and other ceremonial gear. The marchers banged drums and played music as they walked the six-mile (nine-kilometer) route from the capital's City Hall to Stormont, the seat of Northern Ireland's parliament.

Parade-goers carried the orange collarette, a small V-shaped sash worn around the neck. Many also came in the stern-looking dark sunglasses, black bowler caps, and white gloves that have become synonymous with the marches.

At least two women chose a more relaxed uniform: Red-white-and-blue wigs and Union Jack dresses.

The loud and colorful marches date back to the 19th century, and are a longstanding irritant between Northern Ireland's two main religious communities. The loyal orders see them as expressions of their culture and a testament to their faith.

Many Catholics see them as aggressive and anti-Irish, and the marches can devolve into street fights, particularly when they pass through heavily Catholic areas.

There were no immediate reports of any unrest, and marchers passed a potential flashpoint on the parade route — St. Patrick's church near Belfast's city center — without incident.

"They marched with dignity down the road," Father Michael Sheehan, the administrator of St Patrick's, said. "I think a degree of respect was shown that hasn't been shown before."

Nearly every aspect of the marches — from the parade route to the music played — is argued over and litigated by both sides, and a specially-created Parades Commission has been created to mediate between the two. The commission can, for example, re-route a parade around a potential flashpoint or demand that sectarian songs not be sung in certain areas.

The marches are steeped in Northern Ireland's messy history, and Saturday's parade, which had been expected to draw up to 30,000 people, is no different. The march finished at Stormont, with a cultural festival held to commemorate a 1912 proclamation against plans for home rule in Ireland.

Crowd estimates were not immediately available.