Media playback is unsupported on your device Media caption The BBC's Tim Willcox reports as the parade gets under way

Thousands of people have taken part in commemorations in Belfast to mark one of the most significant dates in unionist history.

The six-mile march from central Belfast to Stormont marked the 100th anniversary of the Ulster Covenant, to oppose Home Rule for Ireland in 1912.

There was no trouble at a contentious feeder parade past a north Belfast Catholic church on Saturday morning.

It was the biggest policing operation in the city in 20 years.

A century ago, the signing of the document laid the foundations for the partition of Ireland and the formation of Northern Ireland a decade later.

Restrictions

Northern Ireland's Parades Commission, which makes determinations on contentious marches, had placed restrictions on the part of the route past St Patrick's Church on Donegall Street.

Analysis The huge security operation surrounding the Ulster Covenant parade went better than anyone dared to hope. Yes, there were some unsavoury incidents, but no-one was injured and the vast majority of the 30,000-strong marchers behaved impeccably. The nationalist protesters had their say. The unionist marchers enjoyed their big day. Much of the credit must go to the police. For the 10-year-old Police Service of Northern Ireland, this was their finest hour. Parade bodes well for centenaries Mark Simpson on Twitter What was the Ulster Covenant?

A representative of a nationalist residents group which had contested the ruling said he was glad it had passed off without incident, but claimed the Parades Commission's determination had been breached.

"With one band in particular, the bass drummer danced outside St Patrick's and nobody can work out what type of hymn that was," said Frank Dempsey of the Carrick Hill Residents Association.

"The minute they passed the church, a number of bands reverted to playing (Orange Order song) the Sash and clearly broke the restriction."

The commission also placed the sacred music restriction on bands passing St Matthew's Catholic Church on the Newtownards Road, in the east of the city.

However, this was breached by some bands who played the Sash as they passed the church.

A Parades Commission spokesman said: "Any breach of a determination is a matter for the police to investigate and those involved could be liable to prosecution.

"The commission will take previous behaviour and any breaches into account in reaching future decisions."

The police said evidence had been gathered on Saturday during the parade and said if people had breached the law then they would be reported to the Public Prosecution Service.

The senior officer in charge of the police operation, Assistant Chief Constable Will Kerr, said the aim had been "primarily to ensure the safety of everyone involved".

"The day passed off in relative peace and calm," he said.

"I would like to express my sincere thanks to all of those involved in the hard work behind the scenes over recent weeks, and right up to this evening, to make this possible.

"These very real efforts, made by community representatives and Loyal Orders, supported by their political representatives, show a real willingness to achieve local resolutions.

"Hopefully this will create a more positive platform for dealing with sensitive parades in 2013."

He said a "significant police presence" would remain on duty throughout the weekend to provide "reassurance and support" to local communities.

Up to 30,000 people from eight loyal orders were taking part in the events, including a religious service and celebration at Stormont.

Northern Ireland First Minister Peter Robinson said: "Just as back in 1912, people set aside any differences that they might have within the unionist community, today we're not here as Ulster Unionists or TUV or DUP, we're here simply as unionists."

Media playback is unsupported on your device Media caption Peter Robinson: "You can get a sense of what it must have been like 100 years ago'

The DUP leader added: "It's good to get a sense of the occasion that there must have been 100 years ago, and we have a real expectation that this will be an enjoyable day for all who are taking part in it."

Earlier on Saturday, thousands paraded through Sandy Row in south Belfast, many wearing traditional dress, reminiscent of 1912.

The leader of the Progressive Unionist Party, Billy Hutchinson, addressed the crowd. He told them to "march with pride, march with the wind of history at their back and the spirit of the Ulster Covenant at their core".

Among those at the Stormont event was BNP leader Nick Griffin, who was handing out leaflets.

The feeder parade from Carlisle Circus in north Belfast included 14 bands and six lodges, amounting to around 2,000 people in total.

Part of their route was past St Patrick's Catholic Church on Donegall Street where there has been controversy and violence associated with parades during the summer.

The Parades Commission has ruled that only hymn music is to be played as bands pass the church and has limited any nationalist protest to 150 people.

Last month, seven police officers were injured when trouble broke out after several loyalist bands defied a Parades Commission ruling by playing music as they marched past the church.

The Royal Black Institution, which had organised the 25 August parade, later apologised "for any offence caused" to clergy and parishioners at St Patrick's.

In an open letter, it said its anger was not directed at the Catholic church.

On the Stormont estate, there were a number of covenant exhibitions and displays, and events included performances from the Ulster Scots Folk Orchestra, the Bright Lights Highland Dancers and the County Antrim Fife and Drum.

Image caption The parade passed St Patrick's Church on Donegall Street, amid a huge police presence

Ahead of Saturday's events, the Orange Order said it was expecting a "fun-filled" day.

Dr David Hume, the Order's director of services, said: "This will be a major event and a family day for enjoyment and celebration. We look forward to welcoming people from across Northern Ireland and beyond."

The main parade included members of the loyal orders from England, Scotland and the Irish Republic.