But the River Liffey's natural east-west axis is even more compelling. And, as it happens, it's also Dublin's primary axis in my 'Moss Reid' series of novels. The action tends to take place along this line between the docks and the quays up to Smithfield and Heuston Station, and even further upstream to the Strawberry Beds.
There is a growing movement to regenerate this axis of the city because, as they say, it really is a no-brainer.
Here are a few examples. First up, "The Liffey Quays, A Ribbon Of Green", an excellent TEDxDUBLIN talk by the rather brilliant artist Fergal McCarthy that sums up the main issues and possible solutions...
Next, a slideshow by the architect and lecturer Ciaran Cuffe, who was recently elected a city councillor for the Greens in Stoneybatter. It's his take on the idea of a "Liffey Boulevard" between the Phoenix Park and Dublin Bay.
While the slideshow is taken out of context of his talk and is mostly images with no script, it's easy enough to get the main gist...
Finally, check out Niamh Rabbitt's "Research the City" website for practical ways to do all this rejuvenation and regeneration in gradual steps over four or five years.
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Postscript, 16 June 2015: check out Green Party councillor Ciaran Cuffe's update on the Liffey Cycle Route.