R445: Road of Dreams

My flatmate, an occasional cyclist, recently came back from Ireland where he was attending a family funeral in County Tipperary. He reported that he had driven along a road that was a cyclist's dream: the R445. It runs for 35 km between Limerick and Nenagh with one lane and a wide cycle lane each way. It was the old 'A' Road which has been replaced by a motorway but repaved and in good nick (unlike UK roads.) Apparently the Irish national team has been seen on it. It looks flat (cause Ireland is flat,) straight with very few turn offs. A nice core 25km could be done twice for a 100km TT best.

I think this will take over from the Afsluitdijk in Netherlands as my dream road which might be a bit windy. Maybe one day I will travel to one of these and find out what I can do on a 'pure' road with little or no traffic. Sadly the only thing around here vaguely similar is the Alderley Edge Bypass, which is only 5km. I won't be doing that one 10 times up and down. Anyone know of anything similar in the UK?