The British army will not be deployed on the streets of Belfast for the annual Twelfth demonstrations today for the first time since 1970.
The PSNI hopes the 600-plus parades across Northern Ireland will pass peacefully despite a small number of contentious marches in Belfast and north Antrim.
Military back-up will be available but soldiers still stationed in Belfast will stay in barracks, The Irish Times has learned.
There are more than 3,000 loyalist marches annually in Northern Ireland, about 32 are deemed contentious and are subject to the rulings of the Parades Commission or local agreements.
The largest parade will be in Belfast where lodges from across the city will parade from Carlisle Circus in the north of the city, through the centre and out to Barnett's Park on the southern outskirts.
The demonstration will be addressed by past grand master and former Ulster Unionist MP the Rev Martin Smyth; Robert Saulters, grand master of the Grand Orange Lodge of Ireland, will make the address at the demonstration in Ballycastle, Co Antrim, while Grand Secretary Drew Nelson will make the address in Magherafelt, Co Derry.
Jeffrey Donaldson, DUP MP and a senior Orange member, will speak in Broomhedge, Co Antrim. Other prominent speakers include the order's director of services David Hume who will speak in Bangor, Co Down, and Denis Watson, who will take the platform at Richhill, Co Armagh.
Both these rallies will be among the largest outside Belfast.
Sinn Féin and the SDLP last night appealed for calm amid tentative hopes that the violence witnessed last year at Ardoyne in north Belfast will not be repeated.
Republicans would do all in their power to ensure that the coming days passed off peacefully, Gerry Adams said last night.
"I would once again appeal to people over the coming days, in spite of provocation and in spite of the continuing insistence of the Orange Order to march in areas where they are clearly not welcome, to remain calm," he said.
"As in previous years republicans will do all in our power to ensure that the coming days pass off peacefully, but this is not the sole responsibility of republicans. The British government and the PSNI have a big responsibility. The Orange Order and unionist political leaders must play their part in ensuring that the violence traditionally associated with the Twelfth parades is averted this year."
Former Belfast lord mayor Alex Maskey said: "We have heard much from unionist politicians in recent days about the Twelfth being a celebration of Protestant culture.
"I would challenge them to tell the community in the Short Strand what is cultural about attacks on homes or cultural about the placing of republican heroes and icons on 11th night bonfires for drink and drug-fuelled unionist mobs to dance around."
SDLP deputy leader Alasdair McDonnell called for Parades Commission rulings to be respected and for co-operation with the PSNI. "People should stay away from the obvious flashpoints," he said.
"Despite some recent attempts at a PR charm offensive by the marching orders, it is simply nonsense to portray the Twelfth as a broad community event. It is offensive nonsense to support it with taxpayers' money considering we already pay for the clean-up each year."
He called for a "wider dialogue" to address parades issues and problems.
"We cannot simply go on accepting poisonous bonfires and aggressive flags organised by paramilitaries. We cannot indefinitely accept the flouting of the law and abdication of responsibility by public authorities and the police."