It will take about 3 hours to drive the 296 km. (184 miles).
I have done this in 7 hours driving at an average of 90-100mph stopping only for fuel twice (about 5mins stop each)
the distance from Calais to Biarritz is 1070 km. This is a driving time of nearly ten hours.
I have just completed this journey and it will take approximately 3 hours, depending on weather and traffic it may take longer.
the road distance between Calais and Madrid is 1556 km (967 miles). The driving time is 14H40.