It is a tale of two cities which local politicians should be keen to learn from. Yesterday the centre of Belfast shut down for several hours because of a republican march and the inevitable loyalist protest demonstration.
Hundreds of police officers filled the streets to keep the two sides apart and the professional policing operation was successful.
Yet the image presented was one of a city which was far from at peace with itself and any casual visitor would have found the whole situation quite disturbing.
Contrast that with the situation in Londonderry when the largest demonstration of the year – the Apprentice Boys march – went ahead peacefully.
Not only was it an enjoyable occasion for those directly involved – 7,000 marchers, 144 bands and thousands of supporters – but also a trouble-free day in the city itself.
Of course it was not always like that.
At one time the annual march was always accompanied by violence and protest.
However, gradually a consensus grew in the city that it could not afford to have its economy and reputation continually damaged and serious negotiations took place between the Apprentice Boys, nationalist groups, the police, politicians and the business community.
That transformed the atmosphere and made the demonstration a tourist attraction, rather than an occasion to be avoided at all costs. When we talk of contentious parades during the marching season, these now are largely located in Belfast.
It has become the last place in the province to embrace the idea of meaningful negotiation.
Hardliners on both sides of the divide set the agenda and their ambitions are often incompatible.
Politicians in the city need to engage with each other and across the community using Derry as a model.
Belfast, after all, is the province's capital and the place by which Northern Ireland is often judged and, at present, that produces a very jaundiced vision.
The message to the politicians is clear.
Look west and glimpse what the future can be like.