Why did the bocage appear to surprise Allied forces after the landings?
Short answerThe terrain was known, but the plan expected key road hubs to fall quickly enough to bypass it; unexpected delays let Germany fortify the hedgerows.
NotesThe plan's protection against the hedgerow country depended on taking Carentan, Saint-Lo, and Caen on schedule and opening routes inland. When those timings slipped, German troops gained time to occupy the bocage field by field. The contingency plans did not adequately cover delays as great as those actually encountered. The bocage consisted of earth banks topped with dense vegetation and joined by narrow twisting lanes that forced troops to fight field by field. Units trained in comparable Devon and Cornwall country may have adapted somewhat better, so prior terrain familiarity mattered once the timetable failed.