ATNotts,
In a previous life I lived and worked in Oostende, Luxembourg and Netherlands for some 6 years thus I'm fully familiar with the means of crossing the English Channel, in those days I utilised ferries to/from Oostende, Dunkerque, Calais and on one or two occassions, underground fire permitting, I used the train tunnel.
But none of these are a road, they have yet to build a road tunnel/bridge