On single carriage roads speed limit is 60 mph and on dual carriage way roads the speed limit is 70 mph and on motorways the speed limit is 70 mph. The highway code says these are maximums only in ideal conditions
But I thought it was only 70 mph on dual carriageway roads if there was a central reservation between the two carriageways, otherwise it was still 60 mph....
Jugglering, if there is no central reservation it is a single carriageway regardless of the number of lanes and therefore the national speed limit is 60mph as you say.
Its not even that simple. Scroll to the table at the bottom of this page. http://www.highwaycode.gov.uk/09.htm
I must say I'm with Toureman; how can you drive and not know something as basic as the speed limit?!