These flagship venues will be the standard bearers for the 18 demonstrations on July 12 organised by the Grand Orange Lodge of Ireland. The four locations are Belfast, Dromara, Tandragee and Coleraine.

The Orange Order's director of services Dr David Hume said: "Two years ago we chose Bangor as a flagship Twelfth and more than 80,000 people attended the demonstration.

"We know that nearly half-a-million people enjoy the Twelfth and there is hard evidence that more and more tourists are planning trips to Northern Ireland at that time to coincide with the parades.

The Orange Order has been working closely with the Northern Ireland Tourist Board and Tourism Ireland to attract more visitors in July.

"We cannot thank the tourist authorities enough," Dr Hume said.

"They have shown us their research and made very many useful suggestions which we have taken on board.

"The Twelfth is a unique attraction in Northern Ireland and it brings with it immense benefits to the economy and to everyone in the community. We will be doing everything we can to make the Twelfth attractive for all the family and for anyone – local or visiting – who wants to see it.

"The new battlefield site at the Boyne will also be a major attraction this year and we believe that cultural tourism can play a significant part in the future of Northern Ireland and the Republic of Ireland. The Orange Order is certainly ready to play its part."

The Rossnowlagh parade in Co Donegal will be held on Saturday, July 5, this year and the July 12 demonstrations will be in Belfast, Dromara, Coleraine, Tandragee, Maghera, Kesh, Ballyclare, Omagh, Benburb, Aughnacloy, Derriaghy, Ballymena, Brough-shane, Portavogie, Cullybackey, Kilkeel, Newcastle and Rasharkin.

The Orange Order is also set to unveil a major tourist initiative in the next few weeks, with the publication of the Williamite Trail – a map which follows the route taken by the Williamite Army on the way to victories at the Boyne and Aughrim.