What was the Manstein Plan as noted in the nonfiction book, Lost Victories?

The Manstein Plan was a plan for breaking through on the Western front. It involved funneling a large tank force through the poor roads of the mountainous Ardennes region in Southern Belgium and Luxemburg, crossing the Meuse River in France, and then sweeping north toward the English Channel. Hitler adopted the proposal and the attack was a total success. British and French forces were cut off in Northern France and Belgium.