Archaeological site may be doomed
http://www.irishpost.co.uk/news/story.asp?j=5645&cat=news

"The site of a massive ancient pagan temple unearthed at one of Europe's most archaeologically significant sites will be buried under a controversial motorway, campaigners warned last week."

"Fears were growing that the government is to plough ahead with the contentious M3 route despite the discovery that has excited heritage campaigners."

Tara, County Meath, Ireland, is a neolithic pagan religious center, the seat of the High Kings of Ireland, and a World Heritage site.  Not to mention the focus of countless literary works.  While the Hill of Tara won't be directly threatened, the valley below will be scarred by the highway, which will come within less than a mile of the Hill.  The increased pollution will damage the monuments faster than wind erosion and rain, and the increased access will probably lead to more people visiting it and more likelihood of vandalism. 

I don't disagree that living people will always come before dead people.  I can understand the argument for the Three Gorges Dam in China because it will provide electric power to a lot of people, although the environmental, cultural and social repercussions are overwhelming and barely justifiable.  But a certain measure of conservation of our pasts should kept in mind.  Building a new road where there was already one (albeit smaller one) to relieve traffic but risk damaging significant cultural resources is certainly not a balanced trade-off. 

/soapbox

ETA: some sites about the whole controversy:

General info:
http://en.wikipedia.org/wiki/Hill_of_Tara

Against road construction:
http://www.savetara.com/
http://www.tarawatch.org/

Government site:
http://www.m3motorway.ie/